(Mac) Implement about:memory.

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 5e155a1035a0a555d9c7f50770a90cfccfc146ac..74b32f1976766515b91a3a3c682423fb2f13e2da 100644
--- a/chrome/browser/memory_details.h
+++ b/chrome/browser/memory_details.h
@@ -54,6 +54,10 @@ struct ProcessData {
   ProcessMemoryInformationList processes;
 };
 
+#if defined(OS_MACOSX)
+class ProcessInfoSnapshot;
+#endif
+
 // MemoryDetails fetches memory details about current running browsers.
 // Because this data can only be fetched asynchronously, callers use
 // this class via a callback.
@@ -105,6 +109,15 @@ class MemoryDetails : public base::RefCountedThreadSafe<MemoryDetails> {
   // The parameter holds information about processes from the IO thread.
   void CollectProcessData(std::vector<ProcessMemoryInformation>);
 
+#if defined(OS_MACOSX)
+  // A helper for |CollectProcessData()|, collecting data on a Chrome/Chromium
+  // process.
+  void CollectProcessDataChrome(
+      const std::vector<ProcessMemoryInformation>& child_info,
+      base::ProcessId pid,
+      const ProcessInfoSnapshot& process_info);
+#endif
+
   // Collect child process information on the UI thread.  Information about
   // renderer processes is only available there.
   void CollectChildInfoOnUIThread();