Add renderer memory metrics

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 9185775e4dcc3250f593e95a53a1467b538f5fff..efc5c7b816af63a9818bd102f9d6830ff4d7db57 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -26734,6 +26734,13 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram base="true" name="Memory.Experimental.Renderer" units="MB">
+<!-- Name completed by histogram_suffixes name="RendererMemoryAllocator" -->
+
+  <owner>keishi@chromium.org</owner>
+  <summary>The renderer process's memory usage after a page load.</summary>
+</histogram>
+
 <histogram name="Memory.Extension" units="KB">
   <owner>hajimehoshi@chromium.org</owner>
   <owner>kenjibaheux@google.com</owner>
@@ -115220,6 +115227,40 @@ value.
   <affected-histogram name="Event.Latency.RendererImpl"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="RendererMemoryAllocator" separator=".">
+  <suffix name="BlinkGC" label="Constrained to the BlinkGC allocator"/>

[Ilya Sherman, 2017/01/12 02:17:24]

nit: Please add base="true" for all of these suffixes as well.  base="true" just
means there's no histogram named "Memory.Experimental.Renderer.BlinkGC" -- it's
used a base name that generates actual histogram names via suffixes.

[keishi, 2017/01/12 02:39:11]

Done.

+  <suffix name="Discardable" label="Constrained to discardable memory usage"/>
+  <suffix name="Malloc" label="Constrained to malloc usage"/>
+  <suffix name="NonDiscardableTotalAllocated"
+      label="Summed over the PartitionAlloc, malloc, mainThreadIsolate() and
+             BlinkGC allocators"/>
+  <suffix name="PartitionAlloc"
+      label="Constrained to the PartitionAlloc allocator"/>
+  <suffix name="TotalAllocatedPerRenderView"
+      label="TotalAllocated divided by the number of RenderViews"/>
+  <suffix name="V8MainThreadIsolate"
+      label="Constrained to memory usage by mainThreadIsolate()"/>
+  <suffix name="TotalAllocated"
+      label="Summed over the PartitionAlloc, malloc, discardable memory,
+             mainThreadIsolate() and BlinkGC allocators"/>
+  <affected-histogram name="Memory.Experimental.Renderer"/>
+</histogram_suffixes>
+
+<histogram_suffixes name="RendererMemoryTiming">

[Ilya Sherman, 2017/01/12 02:17:24]

Optional nit: It's fine to use separator="." here too, if you want to keep dots
throughout the name rather than mixing them with underscores.

[keishi, 2017/01/12 02:39:11]

Done.

+  <suffix name="DidFinishLoad" label="DidFinishLoad for all frames"/>

[Ilya Sherman, 2017/01/12 02:17:24]

nit: I'd phrase this label as something like "Recorded each time DidFinishLoad
is called for *any* frame within the page."

[keishi, 2017/01/12 02:39:11]

Done.

+  <suffix name="MainFrameDidFinishLoad" label="DidFinishLoad for main frames"/>
+  <affected-histogram name="Memory.Experimental.Renderer.BlinkGC"/>
+  <affected-histogram name="Memory.Experimental.Renderer.Discardable"/>
+  <affected-histogram name="Memory.Experimental.Renderer.Malloc"/>
+  <affected-histogram
+      name="Memory.Experimental.Renderer.NonDiscardableTotalAllocated"/>
+  <affected-histogram name="Memory.Experimental.Renderer.PartitionAlloc"/>
+  <affected-histogram name="Memory.Experimental.Renderer.TotalAllocated"/>
+  <affected-histogram
+      name="Memory.Experimental.Renderer.TotalAllocatedPerRenderView"/>
+  <affected-histogram name="Memory.Experimental.Renderer.V8MainThreadIsolate"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="RequestMediaKeySystemAccessKeySystems" separator=".">
   <suffix name="ClearKey" label="Requests for the Clear Key key system."/>
   <suffix name="Unknown"