MemoryRelease: take IOS GC branch for WPE

The aim is to make the GC more reliable on low-memory platforms.
In MemoryRelease, the change is to request immediate GC in
releaseCriticalMemory.

Author: tomasz-karczewski-red

Source/WebCore/page/MemoryRelease.cpp

@@ -126,7 +126,7 @@ static void releaseCriticalMemory(Synchronous synchronous, MaintainBackForwardCa
         GCController::singleton().deleteAllCode(JSC::DeleteAllCodeIfNotCollecting);
         GCController::singleton().garbageCollectNow();
     } else {
-#if PLATFORM(IOS_FAMILY)
+#if PLATFORM(IOS_FAMILY) || PLATFORM(WPE)
         GCController::singleton().garbageCollectNowIfNotDoneRecently();
 #else
         GCController::singleton().garbageCollectSoon();