Add a glBegin/End pair to make glBindFramebuffer work

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 6d37175a9853c5cb0de6b2497c781d9828a40530..7ea1a06e73bdf90cbccf38f381c3188bc6d7f7ac 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -4278,6 +4278,14 @@ void GLES2DecoderImpl::SetIgnoreCachedStateForTest(bool ignore) {
 void GLES2DecoderImpl::OnFboChanged() const {
   if (workarounds().restore_scissor_on_fbo_change)
     state_.fbo_binding_for_scissor_workaround_dirty_ = true;
+
+  if (workarounds().gl_begin_gl_end_on_fbo_change_to_backbuffer) {
+    GLint bound_fbo_unsigned = -1;
+    glGetIntegerv(GL_FRAMEBUFFER_BINDING_EXT, &bound_fbo_unsigned);
+    GLuint bound_fbo = static_cast<GLuint>(bound_fbo_unsigned);
+    if (surface_ && surface_->GetBackingFrameBufferObject() == bound_fbo)
+      surface_->NotifyWasBound();
+  }
 }
 
 // Called after the FBO is checked for completeness.