Add renderer memory metrics

content/renderer/render_thread_impl.h

Index: content/renderer/render_thread_impl.h
diff --git a/content/renderer/render_thread_impl.h b/content/renderer/render_thread_impl.h
index 508a1dc00840c1e8468225cf72b31eef4b86e161..b212bfd4899156001a1a4e41ab939fe01e38a0af 100644
--- a/content/renderer/render_thread_impl.h
+++ b/content/renderer/render_thread_impl.h
@@ -481,6 +481,19 @@ class CONTENT_EXPORT RenderThreadImpl
   // ChildMemoryCoordinatorDelegate implementation.
   void OnTrimMemoryImmediately() override;
 
+  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;
+    size_t total_allocated_per_render_view_mb;
+  };
+  void GetRendererMemoryMetrics(
+      RendererMemoryMetrics* memory_metrics) const;
+
  protected:
   RenderThreadImpl(
       const InProcessChildThreadParams& params,