fix about:memory and memory histograms to show extensions more clearly

chrome/browser/memory_details.h

Index: chrome/browser/memory_details.h
diff --git a/chrome/browser/memory_details.h b/chrome/browser/memory_details.h
index b39a1a637c1f37c8fc04e90f5d9b9de4f0c7bb22..9333b56087954ca5317a10b7488dd658df985ad9 100644
--- a/chrome/browser/memory_details.h
+++ b/chrome/browser/memory_details.h
@@ -32,11 +32,14 @@ struct ProcessMemoryInformation {
   string16 product_name;
   // The number of processes which this memory represents.
   int num_processes;
-  // A process is a diagnostics process if it is rendering
-  // about:xxx information.
+  // A process is a diagnostics process if it is rendering about:memory.
+  // Mark this specially so that it can avoid counting it in its own
+  // results.
   bool is_diagnostics;
   // If this is a child process of Chrome, what type (i.e. plugin) it is.
   ChildProcessInfo::ProcessType type;
+  // If this is a renderer process, what type it is.
+  ChildProcessInfo::RendererProcessType renderer_type;
   // A collection of titles used, i.e. for a tab it'll show all the page titles.
   std::vector<string16> titles;
 };