Video Player: Show the appropriate error message on casting unsupported video

Video Player: Show the appropriate error message on casting unsupported video

Previously, the error message was 'An error occurred.' This patch changes it to "This file could not be displayed."

BUG=405860
TEST=manually tested
TBR=fukino@chromium.org

Committed: https://crrev.com/d6768ca8c6658005b3485f4c7a7a167ec49f88fd
Cr-Commit-Position: refs/heads/master@{#292832}

[yoshiki, 2014-08-29 15:30:31]

yoshiki@chromium.org changed reviewers:
+ fukino@chromium.org

[yoshiki, 2014-08-29 15:30:40]

Patchset #1 (id:1) has been deleted

[yoshiki, 2014-08-29 15:31:40]

The CQ bit was checked by yoshiki@chromium.org

[commit-bot: I haz the power, 2014-08-29 15:33:03]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/yoshiki@chromium.org/523663002/20001

[commit-bot: I haz the power, 2014-08-29 16:27:03]

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

[commit-bot: I haz the power, 2014-08-29 16:38:11]

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

[commit-bot: I haz the power, 2014-08-29 16:38:12]

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

[yoshiki, 2014-09-01 04:23:02]

Committed patchset #1 (id:20001) manually as d6768ca (presubmit successful).

[commit-bot: I haz the power, 2014-09-10 03:15:32]

Patchset 1 (id:??) landed as
https://crrev.com/d6768ca8c6658005b3485f4c7a7a167ec49f88fd
Cr-Commit-Position: refs/heads/master@{#292832}