Move ExtensionCache to //extensions

Move ExtensionCache to //extensions

This moves the ExtensionCache interface out to extensions and
delegates instance provisioning out to ExtensionsBrowserClient
implementations.

BUG=398671
Committed: https://crrev.com/1056c8a4ddb699dec826e75358f554c0e4790ae2
Cr-Commit-Position: refs/heads/master@{#299192}

[Ken Rockot(use gerrit already), 2014-10-01 15:28:03]

rockot@chromium.org changed reviewers:
+ asargent@chromium.org

[Ken Rockot(use gerrit already), 2014-10-01 15:29:57]

Antony could you ptal?

I'm not so crazy about having EBC::GetExtensionCache as well as
ExtensionCache::GetInstance, but I thought leaving the ExtensionCache static
interface around was the best compromise in delegating the implementation
without making test overrides painful.

[Ken Rockot(use gerrit already), 2014-10-02 15:36:25]

Patchset #2 (id:20001) has been deleted

[Ken Rockot(use gerrit already), 2014-10-02 17:51:13]

Patchset #1 (id:1) has been deleted

[Ken Rockot(use gerrit already), 2014-10-02 17:51:19]

Patchset #1 (id:40001) has been deleted

[asargent_no_longer_on_chrome, 2014-10-02 22:53:37]

Summary of our in-person conversation about this: I also think it's a little
weird to have 2 top-level ways of getting this object, both
EBC::GetExtensionCache as well as ExtensionCache::GetInstance. 

Maybe we want to expose the idea of registering a test override in EBC?

[Ken Rockot(use gerrit already), 2014-10-06 19:57:44]

Patchset #2 (id:80001) has been deleted

[Ken Rockot(use gerrit already), 2014-10-06 19:58:33]

Alright, I think this works better. It's really only necessary to override the
cache for ExtensionUpdater, so I added the ability to that directly.

[Ken Rockot(use gerrit already), 2014-10-06 20:02:35]

Patchset #2 (id:100001) has been deleted

[Ken Rockot(use gerrit already), 2014-10-06 20:05:02]

Patchset #2 (id:120001) has been deleted

[Ken Rockot(use gerrit already), 2014-10-06 20:23:37]

Patchset #2 (id:140001) has been deleted

[asargent_no_longer_on_chrome, 2014-10-06 23:16:33]

nice, lgtm

https://codereview.chromium.org/612423003/diff/160001/chrome/browser/extensio...
File chrome/browser/extensions/updater/extension_cache_fake.h (right):

https://codereview.chromium.org/612423003/diff/160001/chrome/browser/extensio...
chrome/browser/extensions/updater/extension_cache_fake.h:12: #include
"extensions/browser/updater/extension_cache.h"
Should extension_cache_fake.{h,cc} also move into extensions/browser/updater/ ?
At a quick glance I didn't notice any chrome/ dependencies in here (but might
have missed it)

[Ken Rockot(use gerrit already), 2014-10-09 16:47:51]

The CQ bit was checked by rockot@chromium.org

[commit-bot: I haz the power, 2014-10-09 16:49:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/612423003/180001

[commit-bot: I haz the power, 2014-10-09 17:01:59]

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

[commit-bot: I haz the power, 2014-10-09 17:02:00]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[Ken Rockot(use gerrit already), 2014-10-09 19:14:01]

rockot@chromium.org changed reviewers:
+ pastarmovj@chromium.org

[Ken Rockot(use gerrit already), 2014-10-09 19:14:20]

Julian, could you please take a look at policy_browsertest.cc?

[Ken Rockot(use gerrit already), 2014-10-09 19:15:24]

Patchset #2 (id:160001) has been deleted

[pastarmovj, 2014-10-10 07:41:58]

lgtm

[Ken Rockot(use gerrit already), 2014-10-10 21:25:17]

The CQ bit was checked by rockot@chromium.org

[commit-bot: I haz the power, 2014-10-10 21:25:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/612423003/550001

[commit-bot: I haz the power, 2014-10-10 21:46:18]

Committed patchset #4 (id:550001)

[commit-bot: I haz the power, 2014-10-10 21:46:52]

Patchset 4 (id:??) landed as
https://crrev.com/1056c8a4ddb699dec826e75358f554c0e4790ae2
Cr-Commit-Position: refs/heads/master@{#299192}