Add minimal CalculateIdleState implementation for Android.

Add minimal CalculateIdleState implementation for Android.

It currently just reports that we're active on Android. Further
revisions could check device state to see if we're active but on memory
constrained devices such as Android we'll often get completely killed if
Chrome isn't active. This is a minimal step towards linking Chrome on
Android.

BUG=113487
TEST=


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=122184

[John Grabowski, 2012-02-15 21:48:31]

Plz add much of the CL description as comments in the code.
Add a TODO(yaron) and file a bug to investigate doing this properly.

[commit-bot: I haz the power, 2012-02-15 21:57:26]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a lowly provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[John Grabowski, 2012-02-15 22:04:18]

LGTM

[commit-bot: I haz the power, 2012-02-15 22:05:58]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/yfriedman@chromium.org/9347052/4

[commit-bot: I haz the power, 2012-02-15 23:30:38]

Change committed as 122184