[sync] WebContentsObserver based sessions notifications

chrome/browser/sync/glue/synced_tab_delegate_android.cc

Index: chrome/browser/sync/glue/synced_tab_delegate_android.cc
diff --git a/chrome/browser/sync/glue/synced_tab_delegate_android.cc b/chrome/browser/sync/glue/synced_tab_delegate_android.cc
index 5a72c7f42a2658d5d409d99cdef64551a74b1e48..84ddfb61c0e52164139070c1aae223e8c2d5ca09 100644
--- a/chrome/browser/sync/glue/synced_tab_delegate_android.cc
+++ b/chrome/browser/sync/glue/synced_tab_delegate_android.cc
@@ -36,6 +36,10 @@ bool SyncedTabDelegateAndroid::IsBeingDestroyed() const {
   return tab_contents_delegate_->IsBeingDestroyed();
 }
 
+SessionID::id_type SyncedTabDelegateAndroid::GetSourceTabID() const {
+  return tab_contents_delegate_->GetSourceTabID();
+}
+
 std::string SyncedTabDelegateAndroid::GetExtensionAppId() const {
   return tab_contents_delegate_->GetExtensionAppId();
 }