Renew RasterTaskSchedulingDelayNoAtRasterDecodes UMAs.

Bug: 1140002, 1140003
Test: None
Change-Id: I9ecdcd70aae53c4d891b8754e7087c1a989cb7d6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2485446Reviewed-by: Alexei Svitkine <asvitkine@chromium.org>
Commit-Queue: Alexei Svitkine <asvitkine@chromium.org>
Cr-Commit-Position: refs/heads/master@{#818635}

tools/metrics/histograms/histograms_xml/renderer4/histograms.xml

@@ -22,7 +22,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 <histograms>
 
 <histogram name="Renderer4.Browser.RasterTaskSchedulingDelayNoAtRasterDecodes"
-    units="microseconds" expires_after="2020-11-30">
+    units="microseconds" expires_after="2021-09-30">
   <owner>andrescj@chromium.org</owner>
   <owner>chromeos-gfx@google.com</owner>
   <summary>
@@ -222,7 +222,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="Renderer4.Renderer.RasterTaskSchedulingDelayNoAtRasterDecodes"
-    units="microseconds" expires_after="2020-11-30">
+    units="microseconds" expires_after="2021-09-30">
   <owner>andrescj@chromium.org</owner>
   <owner>chromeos-gfx@google.com</owner>
   <summary>