cros: Log per-process memory use on low memory events

chrome/browser/ui/webui/about_ui.cc

Index: chrome/browser/ui/webui/about_ui.cc
diff --git a/chrome/browser/ui/webui/about_ui.cc b/chrome/browser/ui/webui/about_ui.cc
index 84921a40bdb45ed183df85a5488d32676f708161..ec5942e7281ee60b1e2edb6d4c7f1270c35c2fd9 100644
--- a/chrome/browser/ui/webui/about_ui.cc
+++ b/chrome/browser/ui/webui/about_ui.cc
@@ -573,7 +573,7 @@ std::string AboutDiscardsRun() {
   output.append(StringPrintf("<meta http-equiv=\"refresh\" content=\"2;%s\">",
                              chrome::kChromeUIDiscardsURL));
   output.append(WrapWithTag("p", "Discarding a tab..."));
-  g_browser_process->oom_priority_manager()->DiscardTab();
+  g_browser_process->oom_priority_manager()->LogMemoryAndDiscardTab();
   AppendFooter(&output);
   return output;
 }
@@ -1289,6 +1289,10 @@ void AboutMemoryHandler::AppendProcess(ListValue* child_data,
 
 
 void AboutMemoryHandler::OnDetailsAvailable() {
+  // TODO(jamescook): Do we want to update UMA stats every time the user opens
+  // an about: page, or only do it periodically?
+  UpdateHistograms();
+
   // the root of the JSON hierarchy for about:memory jstemplate
   DictionaryValue root;
   ListValue* browsers = new ListValue();