Add getThemeColor to Tab and add plumbing for ChromeActivites.

Add getThemeColor to Tab and add plumbing for ChromeActivites.

Moves all theme color computing logic to tab. Adds the necessary
update signals to ChromeActivity and adds an onUpdate call to be
overridden by extending classes.

The main outcome of all this is, all ChromeActivities become color change aware. Doesn't add any visual changes. Yet.

BUG=507340
Committed: https://crrev.com/25d23c547cd7661fe2e679d74e4272917dae2985
Cr-Commit-Position: refs/heads/master@{#341226}

[Yusuf, 2015-07-30 20:06:15]

yusufo@chromium.org changed reviewers:
+ dtrainor@chromium.org

[David Trainor- moved to gerrit, 2015-07-30 21:07:46]

lgtm

[Yusuf, 2015-07-30 21:56:35]

I had accidentally removed resetting on interstitial pages and caught that while
running tests.

Would you mind taking a final look?

[David Trainor- moved to gerrit, 2015-07-30 22:16:30]

lgtm

[Yusuf, 2015-07-30 22:19:14]

The CQ bit was checked by yusufo@chromium.org

[commit-bot: I haz the power, 2015-07-30 22:19:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1254423006/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1254423006/20001

[commit-bot: I haz the power, 2015-07-30 22:50:32]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-07-30 22:50:33]

Try jobs failed on following builders:
  android_clang_dbg_recipe on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/android_clang_d...)

[Yusuf, 2015-07-30 23:02:39]

The CQ bit was checked by yusufo@chromium.org

[Yusuf, 2015-07-30 23:02:40]

The patchset sent to the CQ was uploaded after l-g-t-m from
dtrainor@chromium.org
Link to the patchset: https://codereview.chromium.org/1254423006/#ps40001
(title: "Make sure activity exists for referencing resources")

[commit-bot: I haz the power, 2015-07-30 23:03:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1254423006/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1254423006/40001

[commit-bot: I haz the power, 2015-07-30 23:45:50]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-07-30 23:46:41]

Patchset 3 (id:??) landed as
https://crrev.com/25d23c547cd7661fe2e679d74e4272917dae2985
Cr-Commit-Position: refs/heads/master@{#341226}

[Fabrice (no longer in Chrome), 2015-07-31 15:13:33]

A revert of this CL (patchset #3 id:40001) has been created in
https://codereview.chromium.org/1260523004/ by fdegans@chromium.org.

The reason for reverting is: Speculative revert.
This seems to have broken
BrandColorTest.testBrandColorInterstitial
BrandColorTest.testNavigatingToBrandColorAndBack
BrandColorTest.testNoBrandColor
on Lollipop in Document Mde..