Maintain minimal error response.

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 cbd5f871368fe7cc341a3ece6aaea6c4b9b5d4cf..75776d60f1373451852dda3b2fa45f6a89c46f5f 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.cc
+++ b/content/browser/renderer_host/render_widget_host_view_android.cc
@@ -437,7 +437,7 @@ void RenderWidgetHostViewAndroid::GetScaledContentBitmap(
     gfx::Rect src_subrect,
     ReadbackRequestCallback& result_callback) {
   if (!host_ || host_->is_hidden() || !IsSurfaceAvailableForCopy()) {
-    result_callback.Run(SkBitmap(), READBACK_NOT_SUPPORTED);
+    result_callback.Run(SkBitmap(), READBACK_SURFACE_UNAVAILABLE);
     return;
   }
   gfx::Size bounds = layer_->bounds();
@@ -925,7 +925,7 @@ void RenderWidgetHostViewAndroid::CopyFromCompositingSurface(
   }
   base::TimeTicks start_time = base::TimeTicks::Now();
   if (using_browser_compositor_ && !IsSurfaceAvailableForCopy()) {
-    callback.Run(SkBitmap(), READBACK_NOT_SUPPORTED);
+    callback.Run(SkBitmap(), READBACK_SURFACE_UNAVAILABLE);
     return;
   }
   const gfx::Display& display =
@@ -1895,6 +1895,8 @@ void RenderWidgetHostViewAndroid::PrepareTextureCopyOutputResult(
                                                 output_size_in_pixel.height(),
                                                 color_type,
                                                 kOpaque_SkAlphaType))) {
+    scoped_callback_runner.Reset(
+        base::Bind(callback, SkBitmap(), READBACK_BITMAP_ALLOCATION_FAILURE));
     return;
   }