Add comments to HistogramFlatterner interface and rename a function

content/common/child_histogram_message_filter.cc

Index: content/common/child_histogram_message_filter.cc
===================================================================
--- content/common/child_histogram_message_filter.cc	(revision 151415)
+++ content/common/child_histogram_message_filter.cc	(working copy)
@@ -91,7 +91,8 @@
                             problem, base::Histogram::NEVER_EXCEEDED_VALUE);
 }
 
-void ChildHistogramMessageFilter::SnapshotProblemResolved(int amount) {
+void ChildHistogramMessageFilter::InconsistencyDetectedInLoggedCount(
+    int amount) {
   UMA_HISTOGRAM_COUNTS("Histogram.InconsistentSnapshotChildProcess",
                        std::abs(amount));
 }