Remove multiple GC calls and replace GCController.collect calls with GCController.collectAll

LayoutTests/storage/websql/multiple-databases-garbage-collection.js

 function GC()
 {
     // Force GC.
     if (window.GCController)
-        GCController.collect();
+        GCController.collectAll();
     else {
         for (var i = 0; i < 10000; ++i) {
             ({ });
         }
     }
 }
 
 // Variable for the database that will never be forgotten
 var persistentDB = 0;
 // Variable for the forgotten database
@@ skipping 31 matching lines @@
                 tx.executeSql("INSERT INTO DataTest (randomData) VALUES (1)", []);
         }); 
     }, function(err) {
         log("Persistent Database Transaction Errored - " + err);
         checkCompletion();
     }, function() {
         log("Persistent Database Transaction Complete");
         checkCompletion();
     });
 }