Cleanup interaction creation and add ExecuteJavaScript to action_runner.py

ActionRunner API cleanup:
1) BeginInteraction+EndInteraction becomes
    interaction = action_runner.BeginInteraction(...)
    interaction.End()

2) Add action_runner.ExecuteJavaScript.

3) Replaced all existing use cases.

Other cleanups:
1) s/JavascriptAction/JavaScriptAction/
2) s/GetJavascriptMarker/GetJavaScriptMarker/


BUG=361809
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=275341

[nednguyen, 2014-06-05 20:37:02]

lgtm


BeginInteraction(name="...", is_smooth=True)...

[chrishenry, 2014-06-05 21:18:30]

Address TODO as we discussed earlier.

[nednguyen, 2014-06-05 21:21:39]

The CQ bit was checked by nednguyen@google.com

[commit-bot: I haz the power, 2014-06-05 21:23:52]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/chrishenry@google.com/313383002/60001

[dtu, 2014-06-05 22:23:20]

@chromium.org lgtm

[commit-bot: I haz the power, 2014-06-06 01:48:49]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  linux_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_rel/bu...)
  win_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/win_chromium_rel/buil...)

[commit-bot: I haz the power, 2014-06-06 02:45:54]

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

[commit-bot: I haz the power, 2014-06-06 02:45:55]

Try jobs failed on following builders:
  linux_chromium_rel on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/linux_chromium_rel/bu...)

[chrishenry, 2014-06-06 02:49:50]

The CQ bit was checked by chrishenry@google.com

[commit-bot: I haz the power, 2014-06-06 02:52:08]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/chrishenry@google.com/313383002/60001

[commit-bot: I haz the power, 2014-06-06 05:29:25]

Change committed as 275341