Cherry-pick 265870.234@safari-7616-branch (9052a03). https://bugs.web…

…kit.org/show_bug.cgi?id=259836

    heap-use-after-free in WebKit::AudioSessionRoutingArbitratorProxy::logger
    https://bugs.webkit.org/show_bug.cgi?id=259836
    rdar://112774591

    Reviewed by Simon Fraser.

    Move the ALWAYS_LOG() inside the `if (weakThis)` scope since this macro will
    call `this->logger()`.

    * Source/WebKit/UIProcess/Media/cocoa/AudioSessionRoutingArbitratorProxyCocoa.mm:
    (WebKit::AudioSessionRoutingArbitratorProxy::beginRoutingArbitrationWithCategory):

    Canonical link: https://commits.webkit.org/265870.234@safari-7616-branch

Source/WebKit/UIProcess/Media/cocoa/AudioSessionRoutingArbitratorProxyCocoa.mm

@@ -67,9 +67,10 @@
     m_arbitrationStatus = ArbitrationStatus::Pending;
     m_arbitrationUpdateTime = WallTime::now();
     SharedRoutingArbitrator::sharedInstance().beginRoutingArbitrationForToken(m_token, category, [this, weakThis = WeakPtr { *this }, callback = WTFMove(callback), identifier = WTFMove(identifier)] (RoutingArbitrationError error, DefaultRouteChanged routeChanged) mutable {
-        ALWAYS_LOG(identifier, "callback, error = ", error, ", routeChanged = ", routeChanged);
-        if (weakThis)
+        if (weakThis) {
+            ALWAYS_LOG(identifier, "callback, error = ", error, ", routeChanged = ", routeChanged);
             weakThis->m_arbitrationStatus = error == RoutingArbitrationError::None ? ArbitrationStatus::Active : ArbitrationStatus::None;
+        }
         callback(error, routeChanged);
     });
 }