[Sync] Add a new global_id field to sync_pb::TabNavigation

sync/protocol/session_specifics.proto

Index: sync/protocol/session_specifics.proto
diff --git a/sync/protocol/session_specifics.proto b/sync/protocol/session_specifics.proto
index 2438ef66d363d4ccfab060f94529235ef1b674eb..61d2634b90eac1154f37579e1ee88201add40e9e 100644
--- a/sync/protocol/session_specifics.proto
+++ b/sync/protocol/session_specifics.proto
@@ -111,9 +111,6 @@ message TabNavigation {
   optional SyncEnums.PageTransitionRedirectType redirect_type = 7;
   // The unique navigation id (within this client).
   optional int32 unique_id = 8;
-  // Timestamp for when this navigation last occurred (in client time).
-  // If the user goes back/foward in history the timestamp may refresh.
-  optional int64 timestamp = 9;
   // User used the Forward or Back button to navigate among browsing history.
   optional bool navigation_forward_back = 10;
   // User used the address bar to trigger this navigation.
@@ -124,5 +121,12 @@ message TabNavigation {
   optional bool navigation_chain_start = 13;
   // The last transition in a redirect chain.
   optional bool navigation_chain_end = 14;
-}
 
+  // Timestamp for when this navigation last occurred (in milliseconds
+  // since the Unix epoch according to the local clock).  Deprecated
+  // in favor of local_timestamp (which has microsecond resolution).
+  optional int64 timestamp_deprecated = 9;
+  // Timestamp for when this navigation last occurred (in microseconds
+  // since the Windows epoch according to the local clock).
+  optional int64 local_timestamp = 15;

[Nicolas Zea, 2012/10/08 22:20:56]

local_timestamp_us?

Also, any reason why we're switching to windows epoch from unix epoch?

+}