Move version branding to before relocation packing.

Move version branding to before relocation packing.

Objcopy knows nothing about the dynamic tags that point to packed
relocation data.  If objcopy is run after relocation packing, and if it
moves the .android.rel.dyn section, these dynamic tags become invalid
and the crazy linker cannot load the library:

E/chromium_android_linker( 9584): Open:
    Could not open libchrome.2180.0.so:
    Bad packed relocations ident, expected APR1 or APA1

Currently, version branding happens at the end of building libchrome.so,
and after relocation packing.  Re-order so that relocation packing again
comes after all other strip and/or objcopy operations.

BUG=417510

Review URL: https://codereview.chromium.org/621263003

Cr-Commit-Position: refs/heads/master@{#298236}