Reland of Make use of md5_check within process_resources.py

Reland of Make use of md5_check within process_resources.py (patchset #1 id:1 of https://codereview.chromium.org/1370643002/ )

Reason for revert:
Fixed --proguard-file being marked as an input when it's and output. Ensured "all" builds locally.

Original issue's description:
> Revert of Make use of md5_check within process_resources.py (patchset #4 id:60001 of https://codereview.chromium.org/1357663002/ )
>
> Reason for revert:
> breaks compilation, e.g. https://build.chromium.org/p/chromium/builders/Android/builds/46769/steps/compile/logs/stdio
>
> Original issue's description:
> > Make use of md5_check within process_resources.py
> >
> > This stops process_resources being run unnecessarily when only java source files
> > have changed.
> >
> > BUG=533442
> >
> > Committed: https://crrev.com/03f85b7b1ff4f61a76630995709257968d8d7eed
> > Cr-Commit-Position: refs/heads/master@{#350777}
>
> TBR=pkotwicz@chromium.org,agrieve@chromium.org
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=533442
>
> Committed: https://crrev.com/c5cdc35062bd6b16922074b2d8c5c1f8fc905b9c
> Cr-Commit-Position: refs/heads/master@{#350779}

TBR=pkotwicz@chromium.org,jochen@chromium.org
BUG=533442
Committed: https://crrev.com/8a7df3af2f8571d0d9ec0add67e83f5f539ebd25
Cr-Commit-Position: refs/heads/master@{#350840}

[agrieve, 2015-09-25 14:37:15]

Created Reland of Make use of md5_check within process_resources.py

[agrieve, 2015-09-25 14:55:43]

The CQ bit was checked by agrieve@chromium.org

[commit-bot: I haz the power, 2015-09-25 14:55:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1361713003/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1361713003/60001

[commit-bot: I haz the power, 2015-09-25 16:11:16]

Committed patchset #3 (id:60001)

[commit-bot: I haz the power, 2015-09-25 16:11:55]

Patchset 3 (id:??) landed as
https://crrev.com/8a7df3af2f8571d0d9ec0add67e83f5f539ebd25
Cr-Commit-Position: refs/heads/master@{#350840}