Add renderer memory metrics

content/public/renderer/render_thread.h

Index: content/public/renderer/render_thread.h
diff --git a/content/public/renderer/render_thread.h b/content/public/renderer/render_thread.h
index 86e7e9f2f9a4c6650cf73ca011dac54afb49c630..a862bc653bc41ba343109526ad95893303e6eace 100644
--- a/content/public/renderer/render_thread.h
+++ b/content/public/renderer/render_thread.h
@@ -40,6 +40,16 @@ namespace content {
 class RenderThreadObserver;
 class ResourceDispatcherDelegate;
 
+struct RendererMemoryMetrics {
+  size_t partition_alloc_kb;
+  size_t blink_gc_kb;
+  size_t malloc_mb;
+  size_t discardable_kb;
+  size_t v8_main_thread_isolate_mb;
+  size_t total_allocated_mb;
+  size_t non_discardable_total_allocated_mb;
+};
+
 class CONTENT_EXPORT RenderThread : virtual public ChildThread {
  public:
   // Returns the one render thread for this process.  Note that this can only
@@ -104,6 +114,9 @@ class CONTENT_EXPORT RenderThread : virtual public ChildThread {
   // Gets the shutdown event for the process.
   virtual base::WaitableEvent* GetShutdownEvent() = 0;
 
+  virtual void GetRendererMemoryMetrics(
+      RendererMemoryMetrics* memory_metrics) const = 0;
+
   // Retrieve the process ID of the browser process.
   virtual int32_t GetClientId() = 0;
 };