Bug 1432309 - ensure the GL context is current when updating wr. r=sotaro

To avoid future issues, this is done by combining the Render and Update methods
into a single call. As a minor side-effect, timing in the parent method now
includes the time to run update.

MozReview-Commit-ID: GJ0l049eFRj

--HG--
extra : rebase_source : f9b4ee6f34bc45d87b3df40e5a25f3bfb2ec8068

gfx/webrender_bindings/RenderThread.cpp

@@ -220,11 +220,9 @@ RenderThread::UpdateAndRender(wr::WindowId aWindowId)
   }
 
   auto& renderer = it->second;
-  renderer->Update();
-
   TimeStamp start = TimeStamp::Now();
 
-  bool ret = renderer->Render();
+  bool ret = renderer->UpdateAndRender();
   if (!ret) {
     // Render did not happen, do not call NotifyDidRender.
     return;

gfx/webrender_bindings/RendererOGL.cpp

@@ -81,14 +81,8 @@ RendererOGL::GetExternalImageHandler()
   };
 }
 
-void
-RendererOGL::Update()
-{
-  wr_renderer_update(mRenderer);
-}
-
 bool
-RendererOGL::Render()
+RendererOGL::UpdateAndRender()
 {
   uint32_t flags = gfx::gfxVars::WebRenderDebugFlags();
 
@@ -117,6 +111,8 @@ RendererOGL::Render()
     return false;
   }
 
+  wr_renderer_update(mRenderer);
+
   auto size = mCompositor->GetClientSize();
 
   if (!wr_renderer_render(mRenderer, size.width, size.height)) {

gfx/webrender_bindings/RendererOGL.h

@@ -50,10 +50,7 @@ public:
   wr::WrExternalImageHandler GetExternalImageHandler();
 
   /// This can be called on the render thread only.
-  void Update();
-
-  /// This can be called on the render thread only.
-  bool Render();
+  bool UpdateAndRender();
 
   /// This can be called on the render thread only.
   bool RenderToTarget(gfx::DrawTarget& aTarget);