Adds kind-of-live thumbnail generation for a potential tab switcher.

chrome/browser/renderer_host/test_render_view_host.cc

Index: chrome/browser/renderer_host/test_render_view_host.cc
diff --git a/chrome/browser/renderer_host/test_render_view_host.cc b/chrome/browser/renderer_host/test_render_view_host.cc
index 65dd3231bf828fec6d79b32aed6563e06c43e8fe..982beb6ac510458a4869af463139e970aa6f2584 100644
--- a/chrome/browser/renderer_host/test_render_view_host.cc
+++ b/chrome/browser/renderer_host/test_render_view_host.cc
@@ -17,7 +17,7 @@ TestRenderViewHost::TestRenderViewHost(SiteInstance* instance,
     : RenderViewHost(instance, delegate, routing_id, modal_dialog_event),
       render_view_created_(false),
       delete_counter_(NULL) {
-  set_view(new TestRenderWidgetHostView());
+  set_view(new TestRenderWidgetHostView(this));
 }
 
 TestRenderViewHost::~TestRenderViewHost() {
@@ -66,9 +66,14 @@ void TestRenderViewHost::SendNavigate(int page_id, const GURL& url) {
   OnMsgNavigate(msg);
 }
 
+TestRenderWidgetHostView::TestRenderWidgetHostView(RenderWidgetHost* rwh)
+    : rwh_(rwh),
+      is_showing_(false) {
+}
+
 BackingStore* TestRenderWidgetHostView::AllocBackingStore(
     const gfx::Size& size) {
-  return new BackingStore(size);
+  return new BackingStore(rwh_, size);
 }
 
 void RenderViewHostTestHarness::NavigateAndCommit(const GURL& url) {