Fallback to RGBA_8888 if readback format is not supported

content/browser/renderer_host/render_widget_host_view_android.cc

Index: content/browser/renderer_host/render_widget_host_view_android.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_android.cc b/content/browser/renderer_host/render_widget_host_view_android.cc
index f687931630d13362e870a52b05148dbc3da4b7a4..59a51e80533470073e68a679fee28e56f9ce697a 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.cc
+++ b/content/browser/renderer_host/render_widget_host_view_android.cc
@@ -2003,17 +2003,21 @@ void RenderWidgetHostViewAndroid::PrepareTextureCopyOutputResult(
   else
     output_size_in_pixel = dst_size_in_pixel;
 
-  scoped_ptr<SkBitmap> bitmap(new SkBitmap);
-  if (!bitmap->tryAllocPixels(SkImageInfo::Make(output_size_in_pixel.width(),
-                                                output_size_in_pixel.height(),
-                                                color_type,
-                                                kOpaque_SkAlphaType))) {
+  SkColorType preferred_color_type = color_type;

[no sievers, 2015/04/22 20:20:39]

Can we make color_type non-const instead and overwrite it, so we don't
accidentally use the wrong variable somewhere in here?

[patro, 2015/04/23 09:43:46]

Done.

+  GLHelper* gl_helper = GetPostReadbackGLHelper();
+  if (gl_helper) {

[no sievers, 2015/04/22 20:20:39]

nit: if (!gl_helper) return

[patro, 2015/04/23 09:43:46]

Done.

+    if (!gl_helper->IsReadbackConfigSupported(preferred_color_type))
+      preferred_color_type = kRGBA_8888_SkColorType;
+  } else {
     return;
   }
 
-  GLHelper* gl_helper = GetPostReadbackGLHelper();
-  if (!gl_helper || !gl_helper->IsReadbackConfigSupported(color_type))
+  scoped_ptr<SkBitmap> bitmap(new SkBitmap);
+  if (!bitmap->tryAllocPixels(SkImageInfo::Make(
+          output_size_in_pixel.width(), output_size_in_pixel.height(),
+          preferred_color_type, kOpaque_SkAlphaType))) {
     return;
+  }
 
   scoped_ptr<SkAutoLockPixels> bitmap_pixels_lock(
       new SkAutoLockPixels(*bitmap));
@@ -2029,37 +2033,15 @@ void RenderWidgetHostViewAndroid::PrepareTextureCopyOutputResult(
   ignore_result(scoped_callback_runner.Release());
 
   gl_helper->CropScaleReadbackAndCleanMailbox(
-      texture_mailbox.mailbox(),
-      texture_mailbox.sync_point(),
-      result->size(),
-      gfx::Rect(result->size()),
-      output_size_in_pixel,
-      pixels,
-      color_type,
-      base::Bind(&CopyFromCompositingSurfaceFinished,
-                 callback,
-                 base::Passed(&release_callback),
-                 base::Passed(&bitmap),
-                 start_time,
-                 base::Passed(&bitmap_pixels_lock)),
+      texture_mailbox.mailbox(), texture_mailbox.sync_point(), result->size(),
+      gfx::Rect(result->size()), output_size_in_pixel, pixels,
+      preferred_color_type,
+      base::Bind(&CopyFromCompositingSurfaceFinished, callback,
+                 base::Passed(&release_callback), base::Passed(&bitmap),
+                 start_time, base::Passed(&bitmap_pixels_lock)),
       GLHelper::SCALER_QUALITY_GOOD);
 }
 
-SkColorType RenderWidgetHostViewAndroid::PreferredReadbackFormat() {
-  // Define the criteria here. If say the 16 texture readback is
-  // supported we should go with that (this degrades quality)
-  // or stick back to the default format.
-  if (base::SysInfo::IsLowEndDevice()) {
-    // TODO(sievers): Cannot use GLHelper here. Instead remove this API
-    // and have CopyFromCompositingSurface() fall back to RGB8 if 565 was
-    // requested but is not supported.
-    GLHelper* gl_helper = GetPostReadbackGLHelper();
-    if (gl_helper && gl_helper->IsReadbackConfigSupported(kRGB_565_SkColorType))
-      return kRGB_565_SkColorType;
-  }
-  return kN32_SkColorType;
-}
-
 void RenderWidgetHostViewAndroid::OnStylusSelectBegin(float x0,
                                                       float y0,
                                                       float x1,