Files.app: Add UMA for HardUnplugged events.

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 1b9fadd33accac04e02a10acd954c404888363cb..c676a5599148cd8da3a1b09984915df7e7904533 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -9138,6 +9138,22 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="FileBrowser.HardUnpluggedAfterResume" units="milliseconds">

[Alexei Svitkine (slow), 2014/11/25 17:48:12]

Nit: The metric names don't make it sound obvious what's being recorded.

Maybe something like:

FileBrowser.HardUnpluggedAfterResume.TimeSinceSuspend

Same for the other one.

[hirono, 2014/12/02 08:52:43]

Done.

+  <owner>hirono@chromium.org</owner>
+  <summary>
+    Chrome OS File Browser: time from the SuspendDone event to the DiskRemoved
+    event. The UMA is added temporarily for crbug.com/433734.
+  </summary>
+</histogram>
+
+<histogram name="FileBrowser.HardUnpluggedBeforeSuspend" units="milliseconds">
+  <owner>hirono@chromium.org</owner>
+  <summary>
+    Chrome OS File Browser: time from the DiskRemoved event to the Suspend
+    event. The UMA is added temporarily for crbug.com/433734.
+  </summary>
+</histogram>
+
 <histogram name="FileBrowser.Load" units="milliseconds">
   <owner>joshwoodward@google.com</owner>
   <summary>