Bind framebuffer to fbo_ object before readPixels, rather than multisample_fbo_

third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 278 matching lines @@
     return FinishPrepareTextureMailboxSoftware(out_mailbox,
                                                out_release_callback);
   } else {
     return FinishPrepareTextureMailboxGpu(out_mailbox, out_release_callback);
   }
 }
 
 bool DrawingBuffer::FinishPrepareTextureMailboxSoftware(
     cc::TextureMailbox* out_mailbox,
     std::unique_ptr<cc::SingleReleaseCallback>* out_release_callback) {
+  DCHECK(state_restorer_);
   std::unique_ptr<cc::SharedBitmap> bitmap = CreateOrRecycleBitmap();
   if (!bitmap)
     return false;
 
   // Read the framebuffer into |bitmap|.
   {
     unsigned char* pixels = bitmap->pixels();
     DCHECK(pixels);
     bool need_premultiply = want_alpha_channel_ && !premultiplied_alpha_;
     WebGLImageConversion::AlphaOp op =
         need_premultiply ? WebGLImageConversion::kAlphaDoPremultiply
                          : WebGLImageConversion::kAlphaDoNothing;
+    state_restorer_->SetFramebufferBindingDirty();
+    gl_->BindFramebuffer(GL_FRAMEBUFFER, fbo_);
     ReadBackFramebuffer(pixels, Size().Width(), Size().Height(), kReadbackSkia,
                         op);
   }
 
   *out_mailbox = cc::TextureMailbox(bitmap.get(), size_);
   out_mailbox->set_color_space(color_space_);
 
   // This holds a ref on the DrawingBuffer that will keep it alive until the
   // mailbox is released (and while the release callback is running). It also
   // owns the SharedBitmap.
@@ skipping 1056 matching lines @@
   if (pixel_unpack_buffer_binding_dirty_)
     client->DrawingBufferClientRestorePixelUnpackBufferBinding();
 }
 
 bool DrawingBuffer::ShouldUseChromiumImage() {
   return RuntimeEnabledFeatures::webGLImageChromiumEnabled() &&
          chromium_image_usage_ == kAllowChromiumImage;
 }
 
 }  // namespace blink