Quick install skips a lot of the normal install steps in order to
dramatically reduce the installation time [eg Twitter normally takes
20s to install. But, installs in under 2.5s with quick install]
The specific optimizations [with caveats]:
1. Use the JIT. Although the oat file is technically created, it
only contains the exploded contents of the APK and does not contain
pre-compiled native binary code. While this improves install time,
it impacts app execution. [saves 17s]
2. Bypass Play verification. Play normally verifies all installs
to ensure we're not installing malware. But, it can take multiple
seconds for Play to collect and send package information to our
backend servers. [saves 2.7s]
3. Reduce JAR file verification. Due to the structure of the JAR
certs, we cannot completely bypass JAR processing. However we skip
the step of verifying every manifest entry. [saves 1.3s]
NOTE: #2 and #3 will only occur on eng/user-debug builds.
Bug: 22848361
Change-Id: I48e77595ad5c13a9534fdb06da67ba8dae2797fb
27c24fb8b8