Report frequency of single page app navigations to UMA

third_party/WebKit/Source/core/loader/FrameLoaderTypes.h

Index: third_party/WebKit/Source/core/loader/FrameLoaderTypes.h
diff --git a/third_party/WebKit/Source/core/loader/FrameLoaderTypes.h b/third_party/WebKit/Source/core/loader/FrameLoaderTypes.h
index 97a514633ff62dd8ebcc23a2041c7031821d797b..6d2c0c16c29462c035223b753a58ebe0a1b705c8 100644
--- a/third_party/WebKit/Source/core/loader/FrameLoaderTypes.h
+++ b/third_party/WebKit/Source/core/loader/FrameLoaderTypes.h
@@ -101,6 +101,17 @@ enum class ProgressBarCompletion {
   kResourcesBeforeDCLAndSameOriginIFrames
 };
 
+// This enum is used to index different kinds of single-page-application
+// navigations for UMA enum histogram. New enum values can be added, but
+// existing enums must never be renumbered or deleted and reused.
+// This enum should be consistent with SinglePageAppNavigationType in
+// tools/metrics/histograms/enums.

[tdresser, 2017/06/26 15:12:50]

nit: /enums.xml

[Liquan (Max) Gu, 2017/06/26 15:45:11]

Done.

+enum SinglePageAppNavigationType {
+  kSPANavTypeHistoryPushStateOrReplaceState = 0,
+  kSPANavTypeSameDocumentBackwardOrForward = 1,
+  kSPANavTypeOtherFragmentNavigation = 2,
+  kSPANavTypeCount
+};
 }  // namespace blink
 
 #endif