Revert of remove workaround for dx9 angle slow rgba pixel ops

src/gpu/gl/GrGLGpu.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrGLGpu.h"
 #include "GrGLGLSL.h"
@@ skipping 252 matching lines @@
     fCopyProgram.fArrayBuffer = 0;
     fCopyProgram.fProgram = 0;
     if (this->glCaps().shaderCaps()->pathRenderingSupport()) {
         this->glPathRendering()->abandonGpuResources();
     }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 GrPixelConfig GrGLGpu::preferredReadPixelsConfig(GrPixelConfig readConfig,
                                                  GrPixelConfig surfaceConfig) const {
-    if (kMesa_GrGLDriver == this->glContext().driver() &&
-        GrBytesPerPixel(readConfig) == 4 && GrPixelConfigSwapRAndB(readConfig) == surfaceConfig) {
-        // Mesa 3D takes a slow path on when reading back BGRA from an RGBA surface and vice-versa.
-        // Perhaps this should be guarded by some compile-time or runtime check.
+    if (GR_GL_RGBA_8888_PIXEL_OPS_SLOW && kRGBA_8888_GrPixelConfig == readConfig) {
+        return kBGRA_8888_GrPixelConfig;
+    } else if (kMesa_GrGLDriver == this->glContext().driver() &&
+               GrBytesPerPixel(readConfig) == 4 &&
+               GrPixelConfigSwapRAndB(readConfig) == surfaceConfig) {
+        // Mesa 3D takes a slow path on when reading back  BGRA from an RGBA surface and vice-versa.
+        // Perhaps this should be guarded by some compiletime or runtime check.
         return surfaceConfig;
-    } else if (readConfig == kBGRA_8888_GrPixelConfig &&
-               !this->glCaps().readPixelsSupported(this->glInterface(), GR_GL_BGRA,
-                                                   GR_GL_UNSIGNED_BYTE, surfaceConfig)) {
+    } else if (readConfig == kBGRA_8888_GrPixelConfig
+            && !this->glCaps().readPixelsSupported(
+                this->glInterface(),
+                GR_GL_BGRA,
+                GR_GL_UNSIGNED_BYTE,
+                surfaceConfig
+            )) {
         return kRGBA_8888_GrPixelConfig;
     } else {
         return readConfig;
     }
 }
 
 GrPixelConfig GrGLGpu::preferredWritePixelsConfig(GrPixelConfig writeConfig,
                                                   GrPixelConfig surfaceConfig) const {
-    return writeConfig;
+    if (GR_GL_RGBA_8888_PIXEL_OPS_SLOW && kRGBA_8888_GrPixelConfig == writeConfig) {
+        return kBGRA_8888_GrPixelConfig;
+    } else {
+        return writeConfig;
+    }
 }
 
 bool GrGLGpu::canWriteTexturePixels(const GrTexture* texture, GrPixelConfig srcConfig) const {
     if (kIndex_8_GrPixelConfig == srcConfig || kIndex_8_GrPixelConfig == texture->config()) {
         return false;
     }
     if (srcConfig != texture->config() && kGLES_GrGLStandard == this->glStandard()) {
         // In general ES2 requires the internal format of the texture and the format of the src
         // pixels to match. However, It may or may not be possible to upload BGRA data to a RGBA
         // texture. It depends upon which extension added BGRA. The Apple extension allows it
@@ skipping 2795 matching lines @@
             this->setVertexArrayID(gpu, 0);
         }
         int attrCount = gpu->glCaps().maxVertexAttributes();
         if (fDefaultVertexArrayAttribState.count() != attrCount) {
             fDefaultVertexArrayAttribState.resize(attrCount);
         }
         attribState = &fDefaultVertexArrayAttribState;
     }
     return attribState;
 }