[IndexedDB] Adding uma for transaction aborts

tools/metrics/histograms/enums.xml

Index: tools/metrics/histograms/enums.xml
diff --git a/tools/metrics/histograms/enums.xml b/tools/metrics/histograms/enums.xml
index f09bdb34d9ca857edd35d8fc5f3cc69063b3716c..ea994cf80a091f5f6c2cd5052324cf1a2d87b22a 100644
--- a/tools/metrics/histograms/enums.xml
+++ b/tools/metrics/histograms/enums.xml
@@ -18642,6 +18642,16 @@ uploading your change for review.  These are checked by presubmit scripts.
   </int>
 </enum>
 
+<enum name="IDBWebException" type="int">

[jsbell, 2017/05/25 16:52:24]

I'd remove 'Web' here - doesn't add anything

[jsbell, 2017/05/25 17:08:58]

This comment stands.

[dmurph, 2017/05/25 17:33:08]

Done.

+  <int value="0" label="Unknown error"/>
+  <int value="1" label="Constraint error"/>
+  <int value="2" label="Data error"/>
+  <int value="3" label="Version error"/>
+  <int value="4" label="Abort error"/>
+  <int value="5" label="Quota error"/>
+  <int value="6" label="Timeout error"/>
+</enum>
+
 <enum name="IdleSocketFate" type="int">
   <int value="0" label="Reuse: Reused">
     Reusing an idle socket that is previously used.