[Sync] Don't attempt to sync windowless tabs.

chrome/browser/sync/glue/session_model_associator.cc

Index: chrome/browser/sync/glue/session_model_associator.cc
diff --git a/chrome/browser/sync/glue/session_model_associator.cc b/chrome/browser/sync/glue/session_model_associator.cc
index 4b7496d62add66c8175f0c45697334a58938ea29..e3695362b3f8211e6086ae314901fab6c2c513bb 100644
--- a/chrome/browser/sync/glue/session_model_associator.cc
+++ b/chrome/browser/sync/glue/session_model_associator.cc
@@ -216,9 +216,6 @@ void SessionModelAssociator::ReassociateTabs(
 
 void SessionModelAssociator::ReassociateTab(const SyncedTabDelegate& tab) {
   DCHECK(CalledOnValidThread());
-  if (!IsValidTab(tab))
-    return;
-
   int64 sync_id;
   SessionID::id_type id = tab.GetSessionId();
   if (tab.IsBeingDestroyed()) {
@@ -233,6 +230,9 @@ void SessionModelAssociator::ReassociateTab(const SyncedTabDelegate& tab) {
     return;
   }
 
+  if (!IsValidTab(tab))
+    return;
+
   TabLinksMap::const_iterator tablink = tab_map_.find(id);
   if (tablink == tab_map_.end()) {
     // This is a new tab, get a sync node for it.
@@ -251,10 +251,7 @@ void SessionModelAssociator::Associate(const SyncedTabDelegate* tab,
   const SyncedWindowDelegate* window =
       SyncedWindowDelegate::FindSyncedWindowDelegateWithId(
           tab->GetWindowId());
-  if (!window) {  // Can happen for weird things like developer console.
-    tab_pool_.FreeTabNode(sync_id);
-    return;
-  }
+  DCHECK(window);
 
   TabLinks t(sync_id, tab);
   tab_map_[session_id] = t;
@@ -848,7 +845,12 @@ bool SessionModelAssociator::SessionWindowHasNoTabsToSync(
 bool SessionModelAssociator::IsValidTab(const SyncedTabDelegate& tab) {
   DCHECK(CalledOnValidThread());
   if ((tab.profile() == sync_service_->profile() ||
-       sync_service_->profile() == NULL)) {
+       sync_service_->profile() == NULL)) {          // For tests.
+    const SyncedWindowDelegate* window =
+        SyncedWindowDelegate::FindSyncedWindowDelegateWithId(
+            tab.GetWindowId());
+    if (!window)
+      return false;
     const NavigationEntry* entry = tab.GetActiveEntry();
     if (!entry)
       return false;