Added new histogram for analyzing SDCH corruption detection cases.

net/filter/sdch_filter.h

Index: net/filter/sdch_filter.h
diff --git a/net/filter/sdch_filter.h b/net/filter/sdch_filter.h
index 3cea340a9b26d737ab8442ada5e836fced5e2f97..c35ff8db87db6b9b01e1021fb0fb8887d0dadf40 100644
--- a/net/filter/sdch_filter.h
+++ b/net/filter/sdch_filter.h
@@ -54,6 +54,20 @@ class NET_EXPORT_PRIVATE SdchFilter : public Filter {
     PASS_THROUGH,  // Non-sdch content being passed without alteration.
   };
 
+  // Disambiguate various sources for triggering a meta-refresh or failure.
+  enum CorruptionDetectionCause {

[mmenke, 2014/09/05 14:52:27]

This stuff doesn't need to be in the header.  Can just put it in an anonymous
namespace in the cc file.

[Randy Smith (Not in Mondays), 2014/09/07 01:14:16]

Done.

+    RESPONSE_200,
+    RESPONSE_200_CACHED,
+    TENTATIVE_SDCH,
+    TENTATIVE_SDCH_CACHED,
+    DICTIONARY_NOT_FOUND,
+    DICTIONARY_NOT_FOUND_CACHED,
+    NON_SDCH_RESPONSE,
+    NON_SDCH_RESPONSE_CACHED,
+
+    META_REFRESH_CAUSE_MAX,
+  };
+
   // Only to be instantiated by Filter::Factory.
   explicit SdchFilter(const FilterContext& filter_context);
   friend class Filter;
@@ -65,6 +79,10 @@ class NET_EXPORT_PRIVATE SdchFilter : public Filter {
   // specified dest_buffer.
   int OutputBufferExcess(char* const dest_buffer, size_t available_space);
 
+  // Record the particular reason we are falling into the meta-refresh
+  // pathway.
+  void RecordCorruptionDetectionCause(CorruptionDetectionCause cause);
+
   // Context data from the owner of this filter.
   const FilterContext& filter_context_;