Merge 92331 - [chromium] Fix issue where switching composited tabs evicts root textures

Source/WebCore/platform/graphics/chromium/LayerTilerChromium.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 236 matching lines @@
 {
     if (contentRect.isEmpty())
         return;
 
     int left, top, right, bottom;
     contentRectToTileIndices(contentRect, left, top, right, bottom);
 
     for (int j = top; j <= bottom; ++j) {
         for (int i = left; i <= right; ++i) {
             Tile* tile = tileAt(i, j);
-            if (!tile || !tile->texture()->isValid(m_tileSize, GraphicsContext3D::RGBA))
+            if (!tile || !tile->texture()->isValid(m_tileSize, m_textureFormat))
                 continue;
 
-            tile->texture()->reserve(m_tileSize, GraphicsContext3D::RGBA);
+            tile->texture()->reserve(m_tileSize, m_textureFormat);
         }
     }
 }
 
 void LayerTilerChromium::prepareToUpdate(const IntRect& contentRect, LayerTextureUpdater* textureUpdater)
 {
     m_skipsDraw = false;
 
     if (contentRect.isEmpty()) {
         m_updateRect = IntRect();
@@ skipping 357 matching lines @@
     point[6] = quad.p4().x();
     point[7] = quad.p4().y();
     GLC(context, context->uniform2fv(program->vertexShader().pointLocation(), point, 4));
 
     GLC(context, context->drawElements(GraphicsContext3D::TRIANGLES, 6, GraphicsContext3D::UNSIGNED_SHORT, 0));
 }
 
 } // namespace WebCore
 
 #endif // USE(ACCELERATED_COMPOSITING)