Revert "Remove v8::TryCatch from V8StringResource<T>::prepare so that a caller can"

This reverts r172013, it bloated Chrome Linux release ~150K, and others.

TBR=yhirano@chromium.org,haraken@chromium.org
BUG=365265

Review URL: https://codereview.chromium.org/246773002

git-svn-id: svn://svn.chromium.org/blink/trunk@172122 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Plumbing ServiceWorkerGlobalScopeProxy::reportConsoleMessage to WebServiceWorkerContextClient.

BUG=365235

Review URL: https://codereview.chromium.org/244903002

git-svn-id: svn://svn.chromium.org/blink/trunk@172123 bbb929c8-8fbe-4397-9dbb-9b2b20218538