Unit Test for WebView animating in and out of screen

android_webview/browser/hardware_renderer.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "android_webview/browser/hardware_renderer.h"
 
 #include "android_webview/browser/aw_gl_surface.h"
 #include "android_webview/browser/child_frame.h"
 #include "android_webview/browser/deferred_gpu_command_service.h"
 #include "android_webview/browser/parent_compositor_draw_constraints.h"
@@ skipping 187 matching lines @@
   DCHECK(current_context) << "DrawGL called without EGLContext";
 
   // TODO(boliu): Handle context loss.
   if (last_egl_context_ != current_context)
     DLOG(WARNING) << "EGLContextChanged";
 
   gfx::Transform transform(gfx::Transform::kSkipInitialization);
   transform.matrix().setColMajorf(draw_info->transform);
   transform.Translate(scroll_offset_.x(), scroll_offset_.y());
 
+  viewport_.SetSize(draw_info->width, draw_info->height);
   // Need to post the new transform matrix back to child compositor
   // because there is no onDraw during a Render Thread animation, and child
   // compositor might not have the tiles rasterized as the animation goes on.
   ParentCompositorDrawConstraints draw_constraints(
       draw_info->is_layer, transform, gfx::Rect(viewport_));
   if (!child_frame_.get() || draw_constraints.NeedUpdate(*child_frame_)) {
     shared_renderer_state_->PostExternalDrawConstraintsToChildCompositorOnRT(
         draw_constraints);
   }
 
   if (!delegated_layer_.get())
     return;
 
-  viewport_.SetSize(draw_info->width, draw_info->height);
   layer_tree_host_->SetViewportSize(viewport_);
   clip_.SetRect(draw_info->clip_left,
                 draw_info->clip_top,
                 draw_info->clip_right - draw_info->clip_left,
                 draw_info->clip_bottom - draw_info->clip_top);
   stencil_enabled_ = stencil_enabled;
 
   delegated_layer_->SetTransform(transform);
 
   gl_surface_->SetBackingFrameBufferObject(framebuffer_binding_ext);
@@ skipping 21 matching lines @@
 }
 
 void HardwareRenderer::UnusedResourcesAreAvailable() {
   cc::ReturnedResourceArray returned_resources;
   resource_collection_->TakeUnusedResourcesForChildCompositor(
       &returned_resources);
   shared_renderer_state_->InsertReturnedResourcesOnRT(returned_resources);
 }
 
 }  // namespace android_webview