Fix ThemePickerLib for use_resource_processor: true

Reference resources with the package name specified in the manifest
of the library that contains the resources.

Bug: 319160342
Test: m javac-check
Flag: EXEMPT refactor
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:3e0fb7bc5a536363f262b25d36aba2cd4eee7da2)
Merged-In: I2e22dc79c41c32198a6870fc953195a8706fb91c
Change-Id: I2e22dc79c41c32198a6870fc953195a8706fb91c
1 file changed