Tolerate missing AccountManager resource, not just missing resource name

In addition to the primary change in the subject, also some minor cleanup of javadoc, typos, CloseGuard warning, etc found while working on a new AbstractAccountAuthenticator.

Change-Id: I73f3408773a43a0021a15f8d051fd3dbbdf898a5

core/jni/AndroidRuntime.cpp

@@ -907,7 +907,7 @@ void AndroidRuntime::start(const char* className, const bool startSystemServer)
     blockSigpipe();
 
     /* 
-     * 'startSystemServer == true' means runtime is obslete and not run from 
+     * 'startSystemServer == true' means runtime is obsolete and not run from 
      * init.rc anymore, so we print out the boot start event here.
      */
     if (startSystemServer) {