Extend lifetime of some RendererScheduler histograms.

Catan team still uses these, and will be monitoring them in some upcoming experiments.

Change-Id: Id6cda68e5b47cd36b2249bea8cb04bce3dcc2116
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2573461Reviewed-by: Jesse Doherty <jwd@chromium.org>
Reviewed-by: François Doray <fdoray@chromium.org>
Reviewed-by: Alexander Timin <altimin@chromium.org>
Commit-Queue: Chris Hamilton <chrisha@chromium.org>
Cr-Commit-Position: refs/heads/master@{#833772}

tools/metrics/histograms/histograms_xml/renderer/histograms.xml

@@ -211,7 +211,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="RendererScheduler.RendererMainThreadLoad5" units="%"
-    expires_after="M85">
+    expires_after="M95">
   <owner>altimin@chromium.org</owner>
   <summary>
     Renderer main thread load (percentage of time spent in tasks), reported in
@@ -372,7 +372,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="RendererScheduler.TaskDurationPerTaskType2"
-    enum="RendererSchedulerTaskType" expires_after="M85">
+    enum="RendererSchedulerTaskType" expires_after="M95">
   <owner>altimin@chromium.org</owner>
   <owner>hajimehoshi@chromium.org</owner>
   <summary>