Add UMA Histogram Manager to Cronet.

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 91eaf62a08ddaedd23ca826e31c21ce7053f680b..a0c6625d4269b92ea210e9332145c21ed7909001 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -58395,6 +58395,13 @@ To add a new entry, add it with any value and run test to compute valid value.
   <affected-histogram name="PLT.PT_StartToFinish_WithPreview"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="HistogramInconsistencies" separator=".">
+  <suffix name="Cronet" label="Cronet histograms."/>
+  <affected-histogram name="Histogram.InconsistenciesBrowser"/>
+  <affected-histogram name="Histogram.InconsistenciesBrowserUnique"/>
+  <affected-histogram name="Histogram.InconsistentSnapshotBrowser"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="HttpPipeliningCompatibility">
   <suffix name="disable_test" label="Do nothing"/>
   <suffix name="enable_test" label="Test connection for HTTP pipelining"/>