Fix low-memory devices crashing on Chrome start up during UMA recodring

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 e7fae3a454ec0056a365baf82867267a6e83b2e3..c41244fe50e917daa709dfb6376f3875aff44d1e 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -2707,8 +2707,8 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <summary>Is low memory device.</summary>
 </histogram>
 
-<histogram name="ChromiumAndroidLinker.LibraryLoadFromApkSupported"
-    enum="BooleanSupported">

[Ilya Sherman, 2014/10/16 19:00:30]

Normally, I'd encourage you to mark the old histogram as <obsolete> rather than
removing the description.  However, since the histogram was only live for a
couple of days in this case, I suppose it's fine either way.

[petrcermak, 2014/10/17 14:51:28]

Acknowledged.

+<histogram name="ChromiumAndroidLinker.LibraryLoadFromApkSupport"
+    enum="Support">
   <owner>petrcermak@chromium.org</owner>
   <summary>
     Whether the device supports loading a library directly from the APK file.
@@ -39729,11 +39729,6 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <int value="1" label="Success"/>
 </enum>
 
-<enum name="BooleanSupported" type="int">
-  <int value="0" label="Not supported"/>
-  <int value="1" label="Supported"/>
-</enum>
-
 <enum name="BooleanSuppressed" type="int">
   <int value="0" label="No suppressions"/>
   <int value="1" label="Suppressed"/>
@@ -52587,6 +52582,12 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="2" label="Valid response received from the server."/>
 </enum>
 
+<enum name="Support" type="int">

[rmcilroy, 2014/10/17 09:54:45]

If we add LoadedFromApk to this enum then we should probably make the name more
specific to the histogram, and drop the "Supported" from the histogram name
above.

[petrcermak, 2014/10/17 14:51:28]

I changed the name of the enum to "LibraryLoadFromApkSupport" and the possible
values are "Unknown", "Not supported", "Supported", and "Successful". I kept the
histogram as "ChromiumAndroidLinker.LibraryLoadFromApkSupport". However, I am
not completely happy about this so feel free to suggest other names (for the
enum, the histogram, and/or possible values).

+  <int value="0" label="Not supported"/>
+  <int value="1" label="Supported"/>
+  <int value="2" label="Unknown"/>
+</enum>
+
 <enum name="SuspendAttempt" type="int">
   <int value="0" label="Attempted"/>
 </enum>