[Blob] Added error reporting metrics to invalid message errors.

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 4e83b0cac636ed4d644433cf96baff8c8c672554..881c41a7e50af7d30d2c833c6c4cc13fba090626 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -51411,6 +51411,24 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Storage.Blob.InvalidReference" enum="RefcountOperation">
+  <owner>dmurph@chromium.org</owner>
+  <summary>
+    Counts the number of times we have an invalid refcount operation. An invalid
+    increment means the blob didn't exist, and an invalid decrement means we
+    don't have any record of the blob in our host.
+  </summary>
+</histogram>
+
+<histogram name="Storage.Blob.InvalidURLRegister" enum="RefcountOperation">
+  <owner>dmurph@chromium.org</owner>
+  <summary>
+    Counts the number of times we have an invalid url registration operation. An
+    invalid increment means the blob isn't in use by the host yet or the url is
+    already mapped. An invalid decrement means the url isn't registered.
+  </summary>
+</histogram>
+
 <histogram name="Storage.Blob.ItemCount" units="Blob Items">
   <owner>dmurph@chromium.org</owner>
   <summary>
@@ -81423,6 +81441,11 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="9" label="DownloadError"/>
 </enum>
 
+<enum name="RefcountOperation" type="int">
+  <int value="0" label="Decrement"/>
+  <int value="1" label="Increment"/>
+</enum>
+
 <enum name="RemotePlaybackDeviceType" type="int">
   <int value="0" label="Cast Generic Media Player"/>
   <int value="1" label="Cast YouTube Player"/>