Merge changes Ifae9b62e,I2673d2c9

* changes:
  Only load native EGL library if using GL back-end
  Only run ANGLE rules once
diff --git a/opengl/libs/EGL/Loader.cpp b/opengl/libs/EGL/Loader.cpp
index a7fea33..6624976 100644
--- a/opengl/libs/EGL/Loader.cpp
+++ b/opengl/libs/EGL/Loader.cpp
@@ -36,6 +36,7 @@
 #include "egl_platform_entries.h"
 #include "egl_trace.h"
 #include "egldefs.h"
+#include <EGL/eglext_angle.h>
 
 extern "C" {
   android_namespace_t* android_get_exported_namespace(const char*);
@@ -541,6 +542,8 @@
 
     if (use_angle) {
         ALOGV("User set \"Developer Options\" to force the use of ANGLE");
+    } else if (cnx->angleDecided) {
+        use_angle = cnx->useAngle;
     } else {
         // The "Developer Options" value wasn't set to force the use of ANGLE.  Need to temporarily
         // load ANGLE and call the updatable opt-in/out logic:
@@ -610,6 +613,7 @@
             use_angle = false;
             ALOGV("Could not temporarily-load the ANGLE opt-in/out logic, cannot use ANGLE.");
         }
+        cnx->angleDecided = true;
     }
     if (use_angle) {
         so = load_angle_from_namespace(kind, ns);
@@ -618,13 +622,30 @@
     if (so) {
         ALOGV("Loaded ANGLE %s library for %s (instead of native)",
               kind, app_name ? app_name : "nullptr");
-        property_get("debug.angle.backend", prop, "UNSET");
-        ALOGV("ANGLE's backend set to %s", prop);
         property_get("debug.hwui.renderer", prop, "UNSET");
         ALOGV("Skia's renderer set to %s", prop);
         cnx->useAngle = true;
-        // Find and load vendor libEGL for ANGLE
-        if (!cnx->vendorEGL) {
+
+        EGLint angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE;
+
+        char prop[PROPERTY_VALUE_MAX];
+        property_get("debug.angle.backend", prop, "0");
+        switch (atoi(prop)) {
+            case 1:
+                ALOGV("%s: Requesting OpenGLES back-end", __FUNCTION__);
+                angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_OPENGLES_ANGLE;
+                break;
+            case 2:
+                ALOGV("%s: Requesting Vulkan back-end", __FUNCTION__);
+                angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE;
+                break;
+            default:
+                break;
+        }
+
+        cnx->angleBackend = angleBackendDefault;
+        if (!cnx->vendorEGL && (cnx->angleBackend == EGL_PLATFORM_ANGLE_TYPE_OPENGLES_ANGLE)) {
+            // Find and load vendor libEGL for ANGLE's GL back-end to use.
             cnx->vendorEGL = load_system_driver("EGL");
         }
         return so;
diff --git a/opengl/libs/EGL/egl_display.cpp b/opengl/libs/EGL/egl_display.cpp
index 476b304..113f0a6 100644
--- a/opengl/libs/EGL/egl_display.cpp
+++ b/opengl/libs/EGL/egl_display.cpp
@@ -128,56 +128,10 @@
     return sDisplay[uintptr_t(disp)].getPlatformDisplay(disp, attrib_list);
 }
 
-static bool addAnglePlatformAttributes(egl_connection_t* const cnx, const EGLAttrib* attrib_list,
+static bool addAnglePlatformAttributes(egl_connection_t* const cnx,
                                        std::vector<EGLAttrib>& attrs) {
     intptr_t vendorEGL = (intptr_t)cnx->vendorEGL;
 
-    EGLint angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE;
-    if (attrib_list) {
-        while (*attrib_list != EGL_NONE) {
-            EGLAttrib attr = *attrib_list++;
-            EGLAttrib value = *attrib_list++;
-            if (attr == EGL_PLATFORM_ANGLE_TYPE_ANGLE) {
-                switch (value) {
-                    case EGL_PLATFORM_ANGLE_TYPE_DEFAULT_ANGLE:
-                        angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE;
-                        break;
-                    case EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE:
-                    case EGL_PLATFORM_ANGLE_TYPE_OPENGLES_ANGLE:
-                        angleBackendDefault = value;
-                        break;
-                    default:
-                        ALOGW("Invalid EGL_PLATFORM_ANGLE_TYPE_ANGLE attribute: 0x%" PRIxPTR,
-                              value);
-                        break;
-                }
-            }
-        }
-    }
-
-    // Allow debug property to override application's
-    char prop[PROPERTY_VALUE_MAX];
-    property_get("debug.angle.backend", prop, "0");
-    switch (atoi(prop)) {
-        case 1:
-            ALOGV("addAnglePlatformAttributes: Requesting OpenGLES back-end");
-            angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_OPENGLES_ANGLE;
-            break;
-        case 2:
-            ALOGV("addAnglePlatformAttributes: Requesting Vulkan back-end");
-            angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE;
-            break;
-        default:
-            break;
-    }
-
-    if (cnx->angleBackend == 0) {
-        // Haven't been initialized yet, so set it.
-        cnx->angleBackend = angleBackendDefault;
-    } else if (cnx->angleBackend != angleBackendDefault) {
-        return false;
-    }
-
     attrs.reserve(4 * 2);
 
     attrs.push_back(EGL_PLATFORM_ANGLE_TYPE_ANGLE);
@@ -186,6 +140,7 @@
     switch (cnx->angleBackend) {
         case EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE:
             ALOGV("%s: Requesting Vulkan ANGLE back-end", __FUNCTION__);
+            char prop[PROPERTY_VALUE_MAX];
             property_get("debug.angle.validation", prop, "0");
             attrs.push_back(EGL_PLATFORM_ANGLE_DEBUG_LAYERS_ENABLED_ANGLE);
             attrs.push_back(atoi(prop));
@@ -260,7 +215,7 @@
             }
         }
 
-        if (!addAnglePlatformAttributes(cnx, attrib_list, attrs)) {
+        if (!addAnglePlatformAttributes(cnx, attrs)) {
             ALOGE("eglGetDisplay(%p) failed: Mismatch display request", display);
             *error = EGL_BAD_PARAMETER;
             return EGL_NO_DISPLAY;
diff --git a/opengl/libs/EGL/egldefs.h b/opengl/libs/EGL/egldefs.h
index 7c710d5..e19fa38 100644
--- a/opengl/libs/EGL/egldefs.h
+++ b/opengl/libs/EGL/egldefs.h
@@ -76,6 +76,7 @@
     void*               libGles1;
     void*               libGles2;
 
+    bool                angleDecided;
     bool                useAngle;
     EGLint              angleBackend;
     void*               vendorEGL;