Cleanup BrowserPlugin

Cleanup BrowserPlugin

BrowserPluginHostMsg_Attach_Params took in both a size and an origin before this patch.

It seems simpler to pass a view_rect instead.

BUG=none
TBR=kenrb@chromium.org for trivial browser_plugin_messages.h change.

Committed: https://crrev.com/49745bbf3e2dc37bd4218389c9a9c3a610a82889
Cr-Commit-Position: refs/heads/master@{#318096}

[Fady Samuel, 2015-02-25 01:25:28]

fsamuel@chromium.org changed reviewers:
+ paulmeyer@chromium.org

[paulmeyer, 2015-02-25 14:16:14]

lgtm

[Fady Samuel, 2015-02-25 18:43:05]

The CQ bit was checked by fsamuel@chromium.org

[commit-bot: I haz the power, 2015-02-25 18:44:00]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/953243002/1

[commit-bot: I haz the power, 2015-02-25 18:50:10]

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

[commit-bot: I haz the power, 2015-02-25 18:50:11]

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

[Fady Samuel, 2015-02-25 19:01:01]

The CQ bit was checked by fsamuel@chromium.org

[Fady Samuel, 2015-02-25 19:01:01]

The patchset sent to the CQ was uploaded after l-g-t-m from
paulmeyer@chromium.org
Link to the patchset: https://codereview.chromium.org/953243002/#ps20001 (title:
"Rebased")

[commit-bot: I haz the power, 2015-02-25 19:02:16]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/953243002/20001

[commit-bot: I haz the power, 2015-02-25 20:07:39]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-02-25 20:08:07]

Patchset 2 (id:??) landed as
https://crrev.com/49745bbf3e2dc37bd4218389c9a9c3a610a82889
Cr-Commit-Position: refs/heads/master@{#318096}