Revert "[RenderEngine] Rebind output texture when unbinding framebuffer"

This reverts commit d9c717511c46eefa78821a7e326bffde4f02076b.

Reason for revert: Short-term, to unblock emulator users due to
blank app drawer/recents: https://b.corp.google.com/issues/154665573

Bug: b/140158384

Change-Id: Ie3c6500b31eada4bf831ecef1a69c079db4cc61f
diff --git a/libs/renderengine/gl/GLESRenderEngine.cpp b/libs/renderengine/gl/GLESRenderEngine.cpp
index df711d2..da87092 100644
--- a/libs/renderengine/gl/GLESRenderEngine.cpp
+++ b/libs/renderengine/gl/GLESRenderEngine.cpp
@@ -897,32 +897,13 @@
     return glStatus == GL_FRAMEBUFFER_COMPLETE_OES ? NO_ERROR : BAD_VALUE;
 }
 
-void GLESRenderEngine::unbindFrameBuffer(Framebuffer* /*framebuffer*/) {
+void GLESRenderEngine::unbindFrameBuffer(Framebuffer* /* framebuffer */) {
     ATRACE_CALL();
 
     // back to main framebuffer
     glBindFramebuffer(GL_FRAMEBUFFER, 0);
 }
 
-bool GLESRenderEngine::cleanupPostRender() {
-    ATRACE_CALL();
-
-    if (mPriorResourcesCleaned ||
-        (mLastDrawFence != nullptr && mLastDrawFence->getStatus() != Fence::Status::Signaled)) {
-        // If we don't have a prior frame needing cleanup, then don't do anything.
-        return false;
-    }
-
-    // Bind the texture to dummy data so that backing image data can be freed.
-    GLFramebuffer* glFramebuffer = static_cast<GLFramebuffer*>(getFramebufferForDrawing());
-    glFramebuffer->allocateBuffers(1, 1, mPlaceholderDrawBuffer);
-    // Release the cached fence here, so that we don't churn reallocations when
-    // we could no-op repeated calls of this method instead.
-    mLastDrawFence = nullptr;
-    mPriorResourcesCleaned = true;
-    return true;
-}
-
 void GLESRenderEngine::checkErrors() const {
     checkErrors(nullptr);
 }
@@ -1212,13 +1193,7 @@
             // us bad parameters, or we messed up our shader generation).
             return INVALID_OPERATION;
         }
-        mLastDrawFence = nullptr;
-    } else {
-        // The caller takes ownership of drawFence, so we need to duplicate the
-        // fd here.
-        mLastDrawFence = new Fence(dup(drawFence->get()));
     }
-    mPriorResourcesCleaned = false;
 
     checkErrors();
     return NO_ERROR;
diff --git a/libs/renderengine/gl/GLESRenderEngine.h b/libs/renderengine/gl/GLESRenderEngine.h
index 9ab5ee6..d3c94a6 100644
--- a/libs/renderengine/gl/GLESRenderEngine.h
+++ b/libs/renderengine/gl/GLESRenderEngine.h
@@ -17,6 +17,7 @@
 #ifndef SF_GLESRENDERENGINE_H_
 #define SF_GLESRENDERENGINE_H_
 
+#include <stdint.h>
 #include <condition_variable>
 #include <deque>
 #include <mutex>
@@ -75,7 +76,6 @@
                         const std::vector<const LayerSettings*>& layers,
                         const sp<GraphicBuffer>& buffer, const bool useFramebufferCache,
                         base::unique_fd&& bufferFence, base::unique_fd* drawFence) override;
-    bool cleanupPostRender() override;
 
     EGLDisplay getEGLDisplay() const { return mEGLDisplay; }
     // Creates an output image for rendering to
@@ -231,17 +231,6 @@
     std::mutex mRenderingMutex;
 
     std::unique_ptr<Framebuffer> mDrawingBuffer;
-    // this is a 1x1 RGB buffer, but over-allocate in case a driver wants more
-    // memory or if it needs to satisfy alignment requirements. In this case:
-    // assume that each channel requires 4 bytes, and add 3 additional bytes to
-    // ensure that we align on a word. Allocating 16 bytes will provide a
-    // guarantee that we don't clobber memory.
-    uint32_t mPlaceholderDrawBuffer[4];
-    sp<Fence> mLastDrawFence;
-    // Store a separate boolean checking if prior resources were cleaned up, as
-    // devices that don't support native sync fences can't rely on a last draw
-    // fence that doesn't exist.
-    bool mPriorResourcesCleaned = true;
 
     // Blur effect processor, only instantiated when a layer requests it.
     BlurFilter* mBlurFilter = nullptr;
diff --git a/libs/renderengine/gl/GLFramebuffer.cpp b/libs/renderengine/gl/GLFramebuffer.cpp
index 383486b..cb0d5cf 100644
--- a/libs/renderengine/gl/GLFramebuffer.cpp
+++ b/libs/renderengine/gl/GLFramebuffer.cpp
@@ -68,11 +68,11 @@
     return true;
 }
 
-void GLFramebuffer::allocateBuffers(uint32_t width, uint32_t height, void* data) {
+void GLFramebuffer::allocateBuffers(uint32_t width, uint32_t height) {
     ATRACE_CALL();
 
     glBindTexture(GL_TEXTURE_2D, mTextureName);
-    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, nullptr);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_MIRRORED_REPEAT);
diff --git a/libs/renderengine/gl/GLFramebuffer.h b/libs/renderengine/gl/GLFramebuffer.h
index 6757695..b88da3b 100644
--- a/libs/renderengine/gl/GLFramebuffer.h
+++ b/libs/renderengine/gl/GLFramebuffer.h
@@ -39,7 +39,7 @@
 
     bool setNativeWindowBuffer(ANativeWindowBuffer* nativeBuffer, bool isProtected,
                                const bool useFramebufferCache) override;
-    void allocateBuffers(uint32_t width, uint32_t height, void* data = nullptr);
+    void allocateBuffers(uint32_t width, uint32_t height);
     EGLImageKHR getEGLImage() const { return mEGLImage; }
     uint32_t getTextureName() const { return mTextureName; }
     uint32_t getFramebufferName() const { return mFramebufferName; }