Iterative cleanup for GL programs in GPU process

gpu/command_buffer/service/program_manager.h

Index: gpu/command_buffer/service/program_manager.h
diff --git a/gpu/command_buffer/service/program_manager.h b/gpu/command_buffer/service/program_manager.h
index 36bc94e84d1e7f4ce0f7dcd4f9cc6339aeb2471c..67e580f0887e0c847b4f65e855b8e41045401c7d 100644
--- a/gpu/command_buffer/service/program_manager.h
+++ b/gpu/command_buffer/service/program_manager.h
@@ -604,6 +604,11 @@ class GPU_EXPORT ProgramManager {
   // Must call before destruction.
   void Destroy(bool have_context);
 
+  // Can be called before Destroy to perform expensive cleanup. Will run until
+  // currently possible cleanup is performed, or timeout is reached. Returns
+  // true if all possible cleanup has been performed.
+  bool PreDestroyWithTimeout(bool have_context, const base::TimeTicks& timeout);
+
   // Creates a new program.
   Program* CreateProgram(GLuint client_id, GLuint service_id);