Fixed flickering "Computing selection" label.

Fixed flickering "Computing selection" label.

In Files.app, while changing selection "computing selection..." label was shown too frequently causing flickering. This patch simplified the code by removing this redundant label.
Along the way, the panel's contents disappearing has been fixed while changing selection very fast.

TEST=Follow the bug description.
BUG=167799
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=177086

[mtomasz, 2013-01-08 04:57:19]

@dgozman: PTAL.

[mtomasz, 2013-01-11 09:01:00]

@SeRya: PTAL.

[SeRya, 2013-01-11 10:22:22]

Bug suggest to leave prev state for 0.5 sec but CL apparently leaves it as long
as calculation needed. How does it work on Drive+GridView+slow connection?
TableView prefetch metadata agressively so calculation probably always fast.

[mtomasz, 2013-01-15 01:41:07]

https://codereview.chromium.org/11788026/diff/2001/chrome/browser/resources/f...
File chrome/browser/resources/file_manager/js/selection.js (left):

https://codereview.chromium.org/11788026/diff/2001/chrome/browser/resources/f...
chrome/browser/resources/file_manager/js/selection.js:214: var updateDelay =
200;
On 2013/01/11 10:22:22, SeRya wrote:
> Bug suggest to leave prev state for 0.5 sec but CL apparently leaves it as
long
> as calculation needed. How does it work on Drive+GridView+slow connection?
> TableView prefetch metadata agressively so calculation probably always fast.

This should work fine, since label is updated after 200 ms with "Calculating
size..." message. Take a look at line #474. Before, we had duplicated "wating"
messages:
1. Computing selection... (IDS_FILE_BROWSER_COMPUTING_SELECTION) shown
immediately.
2. Calculating size... (IDS_FILE_BROWSER_CALCULATING_SIZE) shown after 200 ms.

I removed the first one since it is redundant and caused flickering.

https://codereview.chromium.org/11788026/diff/2001/chrome/browser/resources/f...
chrome/browser/resources/file_manager/js/selection.js:474:
this.updatePreviewPanelText_();
Here.

[SeRya, 2013-01-15 12:39:45]

lgtm

[commit-bot: I haz the power, 2013-01-15 12:43:49]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mtomasz@chromium.org/11788026/2001

[commit-bot: I haz the power, 2013-01-15 14:13:32]

Retried try job too often on mac_rel for step(s) browser_tests,
content_browsertests, nacl_integration, sync_integration_tests

[commit-bot: I haz the power, 2013-01-16 03:35:25]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/mtomasz@chromium.org/11788026/2001

[commit-bot: I haz the power, 2013-01-16 04:21:37]

Change committed as 177086