PlzNavigate: identify same-page browser-initiated navigation.

content/common/frame_message_enums.h

Index: content/common/frame_message_enums.h
diff --git a/content/common/frame_message_enums.h b/content/common/frame_message_enums.h
index 3d9f84a510f2fcdb3c775c06d1fed12c1f428cdd..ef1d22d0b18e8892038f20795c353cfeb2cd8ba7 100644
--- a/content/common/frame_message_enums.h
+++ b/content/common/frame_message_enums.h
@@ -29,12 +29,36 @@ struct FrameMsg_Navigate_Type {
     // Like RESTORE, except that the navigation contains POST data.
     RESTORE_WITH_POST,
 
-    // Navigation type not categorized by the other types.
-    NORMAL,
+    // History navigation inside the same document.
+    HISTORY_SAME_DOCUMENT,
+
+    // History navigation to a different document.
+    HISTORY_DIFFERENT_DOCUMENT,
+
+    // Navigation inside the same document. It occurs when the part of the url
+    // that is modified is after the '#' part.
+    SAME_DOCUMENT,
+
+    // Navigation to another document.
+    DIFFERENT_DOCUMENT,
 
     // Last guard value, so we can use it for validity checks.
-    NAVIGATE_TYPE_LAST = NORMAL,
+    NAVIGATE_TYPE_LAST = DIFFERENT_DOCUMENT,
   };
+
+  static bool IsReload(Value value) {
+    return value == RELOAD || value == RELOAD_BYPASSING_CACHE ||
+           value == RELOAD_ORIGINAL_REQUEST_URL;
+  }
+
+  static bool IsSameDocument(Value value) {
+    return value == SAME_DOCUMENT || value == HISTORY_SAME_DOCUMENT;
+  }
+
+  static bool IsHistory(Value value) {
+    return value == HISTORY_SAME_DOCUMENT ||
+           value == HISTORY_DIFFERENT_DOCUMENT;
+  }
 };
 
 struct FrameMsg_UILoadMetricsReportType {