Use context.getApplicationInfo()

Due to package install races it is possible for a process to be started from an
old apk even though that apk has been replaced. Querying for ApplicationInfo by
package name may return information for the new apk, leading to a runtime with
the old main dex file and new secondary dex files. This leads to various
problems like ClassNotFoundExceptions. Using context.getApplicationInfo()
should result in the process having a consistent view of the world (even if it
is of the old world). The package install races are eventually resolved and old
processes are killed.

Test: Passes Google Play services tests
Change-Id: I95257d851eb678c55a19e731183f7add2b540615