diff --git a/services/surfaceflinger/RenderEngine/RenderEngine.cpp b/services/surfaceflinger/RenderEngine/RenderEngine.cpp
index 2712b1c..e94200e 100644
--- a/services/surfaceflinger/RenderEngine/RenderEngine.cpp
+++ b/services/surfaceflinger/RenderEngine/RenderEngine.cpp
@@ -184,97 +184,6 @@
     return SyncFeatures::getInstance().useWaitSync();
 }
 
-base::unique_fd RenderEngine::flush() {
-    if (!GLExtensions::getInstance().hasNativeFenceSync()) {
-        return base::unique_fd();
-    }
-
-    EGLSyncKHR sync = eglCreateSyncKHR(mEGLDisplay, EGL_SYNC_NATIVE_FENCE_ANDROID, nullptr);
-    if (sync == EGL_NO_SYNC_KHR) {
-        ALOGW("failed to create EGL native fence sync: %#x", eglGetError());
-        return base::unique_fd();
-    }
-
-    // native fence fd will not be populated until flush() is done.
-    glFlush();
-
-    // get the fence fd
-    base::unique_fd fenceFd(eglDupNativeFenceFDANDROID(mEGLDisplay, sync));
-    eglDestroySyncKHR(mEGLDisplay, sync);
-    if (fenceFd == EGL_NO_NATIVE_FENCE_FD_ANDROID) {
-        ALOGW("failed to dup EGL native fence sync: %#x", eglGetError());
-    }
-
-    return fenceFd;
-}
-
-bool RenderEngine::finish() {
-    if (!GLExtensions::getInstance().hasFenceSync()) {
-        ALOGW("no synchronization support");
-        return false;
-    }
-
-    EGLSyncKHR sync = eglCreateSyncKHR(mEGLDisplay, EGL_SYNC_FENCE_KHR, nullptr);
-    if (sync == EGL_NO_SYNC_KHR) {
-        ALOGW("failed to create EGL fence sync: %#x", eglGetError());
-        return false;
-    }
-
-    EGLint result = eglClientWaitSyncKHR(mEGLDisplay, sync, EGL_SYNC_FLUSH_COMMANDS_BIT_KHR,
-                                         2000000000 /*2 sec*/);
-    EGLint error = eglGetError();
-    eglDestroySyncKHR(mEGLDisplay, sync);
-    if (result != EGL_CONDITION_SATISFIED_KHR) {
-        if (result == EGL_TIMEOUT_EXPIRED_KHR) {
-            ALOGW("fence wait timed out");
-        } else {
-            ALOGW("error waiting on EGL fence: %#x", error);
-        }
-        return false;
-    }
-
-    return true;
-}
-
-bool RenderEngine::waitFence(base::unique_fd fenceFd) {
-    if (!GLExtensions::getInstance().hasNativeFenceSync() ||
-        !GLExtensions::getInstance().hasWaitSync()) {
-        return false;
-    }
-
-    EGLint attribs[] = {EGL_SYNC_NATIVE_FENCE_FD_ANDROID, fenceFd, EGL_NONE};
-    EGLSyncKHR sync = eglCreateSyncKHR(mEGLDisplay, EGL_SYNC_NATIVE_FENCE_ANDROID, attribs);
-    if (sync == EGL_NO_SYNC_KHR) {
-        ALOGE("failed to create EGL native fence sync: %#x", eglGetError());
-        return false;
-    }
-
-    // fenceFd is now owned by EGLSync
-    (void)fenceFd.release();
-
-    // XXX: The spec draft is inconsistent as to whether this should return an
-    // EGLint or void.  Ignore the return value for now, as it's not strictly
-    // needed.
-    eglWaitSyncKHR(mEGLDisplay, sync, 0);
-    EGLint error = eglGetError();
-    eglDestroySyncKHR(mEGLDisplay, sync);
-    if (error != EGL_SUCCESS) {
-        ALOGE("failed to wait for EGL native fence sync: %#x", error);
-        return false;
-    }
-
-    return true;
-}
-
-void RenderEngine::checkErrors() const {
-    do {
-        // there could be more than one error flag
-        GLenum error = glGetError();
-        if (error == GL_NO_ERROR) break;
-        ALOGE("GL error 0x%04x", int(error));
-    } while (true);
-}
-
 RenderEngine::GlesVersion RenderEngine::parseGlesVersion(const char* str) {
     int major, minor;
     if (sscanf(str, "OpenGL ES-CM %d.%d", &major, &minor) != 2) {
@@ -293,56 +202,6 @@
     return GLES_VERSION_1_0;
 }
 
-void RenderEngine::fillRegionWithColor(const Region& region, uint32_t height, float red,
-                                       float green, float blue, float alpha) {
-    size_t c;
-    Rect const* r = region.getArray(&c);
-    Mesh mesh(Mesh::TRIANGLES, c * 6, 2);
-    Mesh::VertexArray<vec2> position(mesh.getPositionArray<vec2>());
-    for (size_t i = 0; i < c; i++, r++) {
-        position[i * 6 + 0].x = r->left;
-        position[i * 6 + 0].y = height - r->top;
-        position[i * 6 + 1].x = r->left;
-        position[i * 6 + 1].y = height - r->bottom;
-        position[i * 6 + 2].x = r->right;
-        position[i * 6 + 2].y = height - r->bottom;
-        position[i * 6 + 3].x = r->left;
-        position[i * 6 + 3].y = height - r->top;
-        position[i * 6 + 4].x = r->right;
-        position[i * 6 + 4].y = height - r->bottom;
-        position[i * 6 + 5].x = r->right;
-        position[i * 6 + 5].y = height - r->top;
-    }
-    setupFillWithColor(red, green, blue, alpha);
-    drawMesh(mesh);
-}
-
-void RenderEngine::clearWithColor(float red, float green, float blue, float alpha) {
-    glClearColor(red, green, blue, alpha);
-    glClear(GL_COLOR_BUFFER_BIT);
-}
-
-void RenderEngine::setScissor(uint32_t left, uint32_t bottom, uint32_t right, uint32_t top) {
-    glScissor(left, bottom, right, top);
-    glEnable(GL_SCISSOR_TEST);
-}
-
-void RenderEngine::disableScissor() {
-    glDisable(GL_SCISSOR_TEST);
-}
-
-void RenderEngine::genTextures(size_t count, uint32_t* names) {
-    glGenTextures(count, names);
-}
-
-void RenderEngine::deleteTextures(size_t count, uint32_t const* names) {
-    glDeleteTextures(count, names);
-}
-
-void RenderEngine::readPixels(size_t l, size_t b, size_t w, size_t h, uint32_t* pixels) {
-    glReadPixels(l, b, w, h, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
-}
-
 void RenderEngine::dump(String8& result) {
     const GLExtensions& extensions = GLExtensions::getInstance();
 
diff --git a/services/surfaceflinger/RenderEngine/gl/GLES20RenderEngine.cpp b/services/surfaceflinger/RenderEngine/gl/GLES20RenderEngine.cpp
index bfabf4d..61df675 100644
--- a/services/surfaceflinger/RenderEngine/gl/GLES20RenderEngine.cpp
+++ b/services/surfaceflinger/RenderEngine/gl/GLES20RenderEngine.cpp
@@ -34,6 +34,7 @@
 #include <ui/ColorSpace.h>
 #include <ui/DebugUtils.h>
 #include <ui/Rect.h>
+#include <ui/Region.h>
 #include <utils/String8.h>
 #include <utils/Trace.h>
 #include "GLExtensions.h"
@@ -195,6 +196,134 @@
     eglMakeCurrent(mEGLDisplay, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
 }
 
+base::unique_fd GLES20RenderEngine::flush() {
+    if (!GLExtensions::getInstance().hasNativeFenceSync()) {
+        return base::unique_fd();
+    }
+
+    EGLSyncKHR sync = eglCreateSyncKHR(mEGLDisplay, EGL_SYNC_NATIVE_FENCE_ANDROID, nullptr);
+    if (sync == EGL_NO_SYNC_KHR) {
+        ALOGW("failed to create EGL native fence sync: %#x", eglGetError());
+        return base::unique_fd();
+    }
+
+    // native fence fd will not be populated until flush() is done.
+    glFlush();
+
+    // get the fence fd
+    base::unique_fd fenceFd(eglDupNativeFenceFDANDROID(mEGLDisplay, sync));
+    eglDestroySyncKHR(mEGLDisplay, sync);
+    if (fenceFd == EGL_NO_NATIVE_FENCE_FD_ANDROID) {
+        ALOGW("failed to dup EGL native fence sync: %#x", eglGetError());
+    }
+
+    return fenceFd;
+}
+
+bool GLES20RenderEngine::finish() {
+    if (!GLExtensions::getInstance().hasFenceSync()) {
+        ALOGW("no synchronization support");
+        return false;
+    }
+
+    EGLSyncKHR sync = eglCreateSyncKHR(mEGLDisplay, EGL_SYNC_FENCE_KHR, nullptr);
+    if (sync == EGL_NO_SYNC_KHR) {
+        ALOGW("failed to create EGL fence sync: %#x", eglGetError());
+        return false;
+    }
+
+    EGLint result = eglClientWaitSyncKHR(mEGLDisplay, sync, EGL_SYNC_FLUSH_COMMANDS_BIT_KHR,
+                                         2000000000 /*2 sec*/);
+    EGLint error = eglGetError();
+    eglDestroySyncKHR(mEGLDisplay, sync);
+    if (result != EGL_CONDITION_SATISFIED_KHR) {
+        if (result == EGL_TIMEOUT_EXPIRED_KHR) {
+            ALOGW("fence wait timed out");
+        } else {
+            ALOGW("error waiting on EGL fence: %#x", error);
+        }
+        return false;
+    }
+
+    return true;
+}
+
+bool GLES20RenderEngine::waitFence(base::unique_fd fenceFd) {
+    if (!GLExtensions::getInstance().hasNativeFenceSync() ||
+        !GLExtensions::getInstance().hasWaitSync()) {
+        return false;
+    }
+
+    EGLint attribs[] = {EGL_SYNC_NATIVE_FENCE_FD_ANDROID, fenceFd, EGL_NONE};
+    EGLSyncKHR sync = eglCreateSyncKHR(mEGLDisplay, EGL_SYNC_NATIVE_FENCE_ANDROID, attribs);
+    if (sync == EGL_NO_SYNC_KHR) {
+        ALOGE("failed to create EGL native fence sync: %#x", eglGetError());
+        return false;
+    }
+
+    // fenceFd is now owned by EGLSync
+    (void)fenceFd.release();
+
+    // XXX: The spec draft is inconsistent as to whether this should return an
+    // EGLint or void.  Ignore the return value for now, as it's not strictly
+    // needed.
+    eglWaitSyncKHR(mEGLDisplay, sync, 0);
+    EGLint error = eglGetError();
+    eglDestroySyncKHR(mEGLDisplay, sync);
+    if (error != EGL_SUCCESS) {
+        ALOGE("failed to wait for EGL native fence sync: %#x", error);
+        return false;
+    }
+
+    return true;
+}
+
+void GLES20RenderEngine::fillRegionWithColor(const Region& region, uint32_t height, float red,
+                                             float green, float blue, float alpha) {
+    size_t c;
+    Rect const* r = region.getArray(&c);
+    Mesh mesh(Mesh::TRIANGLES, c * 6, 2);
+    Mesh::VertexArray<vec2> position(mesh.getPositionArray<vec2>());
+    for (size_t i = 0; i < c; i++, r++) {
+        position[i * 6 + 0].x = r->left;
+        position[i * 6 + 0].y = height - r->top;
+        position[i * 6 + 1].x = r->left;
+        position[i * 6 + 1].y = height - r->bottom;
+        position[i * 6 + 2].x = r->right;
+        position[i * 6 + 2].y = height - r->bottom;
+        position[i * 6 + 3].x = r->left;
+        position[i * 6 + 3].y = height - r->top;
+        position[i * 6 + 4].x = r->right;
+        position[i * 6 + 4].y = height - r->bottom;
+        position[i * 6 + 5].x = r->right;
+        position[i * 6 + 5].y = height - r->top;
+    }
+    setupFillWithColor(red, green, blue, alpha);
+    drawMesh(mesh);
+}
+
+void GLES20RenderEngine::clearWithColor(float red, float green, float blue, float alpha) {
+    glClearColor(red, green, blue, alpha);
+    glClear(GL_COLOR_BUFFER_BIT);
+}
+
+void GLES20RenderEngine::setScissor(uint32_t left, uint32_t bottom, uint32_t right, uint32_t top) {
+    glScissor(left, bottom, right, top);
+    glEnable(GL_SCISSOR_TEST);
+}
+
+void GLES20RenderEngine::disableScissor() {
+    glDisable(GL_SCISSOR_TEST);
+}
+
+void GLES20RenderEngine::genTextures(size_t count, uint32_t* names) {
+    glGenTextures(count, names);
+}
+
+void GLES20RenderEngine::deleteTextures(size_t count, uint32_t const* names) {
+    glDeleteTextures(count, names);
+}
+
 void GLES20RenderEngine::bindExternalTextureImage(uint32_t texName,
                                                   const Image& image) {
     const GLImage& glImage = static_cast<const GLImage&>(image);
@@ -207,6 +336,10 @@
     }
 }
 
+void GLES20RenderEngine::readPixels(size_t l, size_t b, size_t w, size_t h, uint32_t* pixels) {
+    glReadPixels(l, b, w, h, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
+}
+
 status_t GLES20RenderEngine::bindFrameBuffer(Framebuffer* framebuffer) {
     GLFramebuffer* glFramebuffer = static_cast<GLFramebuffer*>(framebuffer);
     EGLImageKHR eglImage = glFramebuffer->getEGLImage();
@@ -245,6 +378,15 @@
     disableScissor();
 }
 
+void GLES20RenderEngine::checkErrors() const {
+    do {
+        // there could be more than one error flag
+        GLenum error = glGetError();
+        if (error == GL_NO_ERROR) break;
+        ALOGE("GL error 0x%04x", int(error));
+    } while (true);
+}
+
 void GLES20RenderEngine::setViewportAndProjection(size_t vpw, size_t vph, Rect sourceCrop,
                                                   ui::Transform::orientation_flags rotation) {
     int32_t l = sourceCrop.left;
diff --git a/services/surfaceflinger/RenderEngine/gl/GLES20RenderEngine.h b/services/surfaceflinger/RenderEngine/gl/GLES20RenderEngine.h
index 3113e53..04dc1b1 100644
--- a/services/surfaceflinger/RenderEngine/gl/GLES20RenderEngine.h
+++ b/services/surfaceflinger/RenderEngine/gl/GLES20RenderEngine.h
@@ -48,14 +48,24 @@
     std::unique_ptr<Image> createImage() override;
 
     void primeCache() const override;
-
-    bool isCurrent() const;
+    bool isCurrent() const override;
     bool setCurrentSurface(const Surface& surface) override;
     void resetCurrentSurface() override;
-
+    base::unique_fd flush() override;
+    bool finish() override;
+    bool waitFence(base::unique_fd fenceFd) override;
+    void clearWithColor(float red, float green, float blue, float alpha) override;
+    void fillRegionWithColor(const Region& region, uint32_t height, float red, float green,
+                                     float blue, float alpha) override;
+    void setScissor(uint32_t left, uint32_t bottom, uint32_t right, uint32_t top) override;
+    void disableScissor() override;
+    void genTextures(size_t count, uint32_t* names) override;
+    void deleteTextures(size_t count, uint32_t const* names) override;
     void bindExternalTextureImage(uint32_t texName, const Image& image) override;
+    void readPixels(size_t l, size_t b, size_t w, size_t h, uint32_t* pixels) override;
     status_t bindFrameBuffer(Framebuffer* framebuffer) override;
     void unbindFrameBuffer(Framebuffer* framebuffer) override;
+    void checkErrors() const override;
 
 protected:
     void dump(String8& result) override;
diff --git a/services/surfaceflinger/RenderEngine/gl/Program.cpp b/services/surfaceflinger/RenderEngine/gl/Program.cpp
index 4d6839b..c8d6cf9 100644
--- a/services/surfaceflinger/RenderEngine/gl/Program.cpp
+++ b/services/surfaceflinger/RenderEngine/gl/Program.cpp
@@ -20,7 +20,6 @@
 
 #include <log/log.h>
 #include <math/mat4.h>
-#include <renderengine/private/Description.h>
 #include <utils/String8.h>
 #include "ProgramCache.h"
 
diff --git a/services/surfaceflinger/RenderEngine/include/renderengine/RenderEngine.h b/services/surfaceflinger/RenderEngine/include/renderengine/RenderEngine.h
index 7777202..86a1264 100644
--- a/services/surfaceflinger/RenderEngine/include/renderengine/RenderEngine.h
+++ b/services/surfaceflinger/RenderEngine/include/renderengine/RenderEngine.h
@@ -25,8 +25,8 @@
 #include <EGL/eglext.h>
 #include <android-base/unique_fd.h>
 #include <math/mat4.h>
-#include <renderengine/Image.h>
 #include <renderengine/Framebuffer.h>
+#include <renderengine/Image.h>
 #include <ui/GraphicTypes.h>
 #include <ui/Transform.h>
 
@@ -105,7 +105,7 @@
     virtual void unbindFrameBuffer(Framebuffer* framebuffer) = 0;
 
     // set-up
-    virtual void checkErrors() const;
+    virtual void checkErrors() const = 0;
     virtual void setViewportAndProjection(size_t vpw, size_t vph, Rect sourceCrop,
                                           ui::Transform::orientation_flags rotation) = 0;
     virtual void setupLayerBlending(bool premultipliedAlpha, bool opaque, bool disableTexture,
@@ -188,33 +188,6 @@
     bool useNativeFenceSync() const override;
     bool useWaitSync() const override;
 
-    // synchronization
-
-    // flush submits RenderEngine command stream for execution and returns a
-    // native fence fd that is signaled when the execution has completed.  It
-    // returns -1 on errors.
-    base::unique_fd flush() override;
-    // finish waits until RenderEngine command stream has been executed.  It
-    // returns false on errors.
-    bool finish() override;
-    // waitFence inserts a wait on an external fence fd to RenderEngine
-    // command stream.  It returns false on errors.
-    bool waitFence(base::unique_fd fenceFd) override;
-
-    // helpers
-    void clearWithColor(float red, float green, float blue, float alpha) override;
-    void fillRegionWithColor(const Region& region, uint32_t height, float red, float green,
-                             float blue, float alpha) override;
-
-    // common to all GL versions
-    void setScissor(uint32_t left, uint32_t bottom, uint32_t right, uint32_t top) override;
-    void disableScissor() override;
-    void genTextures(size_t count, uint32_t* names) override;
-    void deleteTextures(size_t count, uint32_t const* names) override;
-    void readPixels(size_t l, size_t b, size_t w, size_t h, uint32_t* pixels) override;
-
-    void checkErrors() const override;
-
     void setupColorTransform(const mat4& /* colorTransform */) override {}
 
     // internal to RenderEngine