PatchSequenceApply: Expose API to allow apply one patch a time

Modify applyPatchSequenceByInstallName to apply just specified
patch.

Modify return values of installing patch APIs to report patch is
already installed.

Change-Id: I964bb8002691e91627cc55bf187b60d6624d3f06
Merge "PatchSequenceApply: Expose API to allow apply one patch a time"