Wait for the GPU info to be collected.

chrome/browser/gpu_process_host_ui_shim.h

Index: chrome/browser/gpu_process_host_ui_shim.h
===================================================================
--- chrome/browser/gpu_process_host_ui_shim.h	(revision 69024)
+++ chrome/browser/gpu_process_host_ui_shim.h	(working copy)
@@ -11,7 +11,9 @@
 // portion of this class, the GpuProcessHost, is responsible for
 // shuttling messages between the browser and GPU processes.
 
+#include "base/callback.h"
 #include "base/non_thread_safe.h"
+#include "base/scoped_ptr.h"
 #include "base/singleton.h"
 #include "chrome/common/gpu_info.h"
 #include "chrome/common/message_router.h"
@@ -54,6 +56,13 @@
   // Return all known information about the GPU.
   const GPUInfo& gpu_info() const;
 
+  // Used only in testing. Sets a callback to invoke when GPU info is collected,
+  // regardless of whether it has been collected already or if it is partial
+  // or complete info. Set to NULL when the callback should no longer be called.
+  void set_gpu_info_collected_callback(Callback0::Type* callback) {
+    gpu_info_collected_callback_.reset(callback);
+  }
+
  private:
   friend struct DefaultSingletonTraits<GpuProcessHostUIShim>;
 
@@ -70,6 +79,10 @@
   GPUInfo gpu_info_;
 
   MessageRouter router_;
+
+  // Used only in testing. If set, the callback is invoked when the GPU info
+  // has been collected.
+  scoped_ptr<Callback0::Type> gpu_info_collected_callback_;
 };
 
 #endif  // CHROME_BROWSER_GPU_PROCESS_HOST_UI_SHIM_H_