Bind framebuffer to fbo_ object before readPixels, rather than multisample_fbo_

third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp

Index: third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp b/third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp
index acc92e22430d2df5e5482c13dd16b6208523f9ef..944abccd57353da75a6d16f166ab574c14fa5c1b 100644
--- a/third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp
+++ b/third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.cpp
@@ -296,6 +296,7 @@ bool DrawingBuffer::PrepareTextureMailboxInternal(
 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;
@@ -308,6 +309,8 @@ bool DrawingBuffer::FinishPrepareTextureMailboxSoftware(
     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);
   }