Only Update the Scale Factor if the Scale Factor Actually Changed

Only Update the Scale Factor if the Scale Factor Actually Changed

WM_DPICHANGED may fire when the DPI hasn't actually changed. This occurs
during initialization with an interaction from EnableChildWindowDpiMessage.
For maximized windows, this causes the bounds logic to unset WS_MAXIMIZE from
the HWND, which leads to WM_SYSCOMMAND with SC_MAXIMIZE prematurely showing the
window, and short-circuting BrowserView::Show() causing it to skip showing the
contents of the window because the frame is already visible.

BUG=625076
Committed: https://crrev.com/8e164fb9b1df48c5e01540190a108eaaad86feca
Cr-Commit-Position: refs/heads/master@{#406962}

[robliao, 2016-07-21 00:39:26]

The CQ bit was checked by robliao@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-07-21 00:39:51]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-21 02:22:01]

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

[commit-bot: I haz the power, 2016-07-21 02:22:02]

Dry run: Try jobs failed on following builders:
  win_chromium_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_...)

[robliao, 2016-07-21 16:55:11]

The CQ bit was checked by robliao@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-07-21 16:55:39]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[robliao, 2016-07-21 16:56:26]

robliao@chromium.org changed reviewers:
+ oshima@chromium.org, sky@chromium.org

[robliao, 2016-07-21 16:56:27]

Reviewers: Please review the file patterns by your name. Thanks!

oshima: ui/display/*
sky: ui/views/*

[commit-bot: I haz the power, 2016-07-21 17:39:15]

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

[commit-bot: I haz the power, 2016-07-21 17:39:16]

Dry run: This issue passed the CQ dry run.

[sky, 2016-07-21 19:26:32]

LGTM

[oshima, 2016-07-21 22:03:14]

lgtm

[robliao, 2016-07-21 22:03:37]

The CQ bit was checked by robliao@chromium.org

[commit-bot: I haz the power, 2016-07-21 22:04:14]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-21 22:09:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-07-21 22:11:09]

Description was changed from

==========
Only Update the Scale Factor if the Scale Factor Actually Changed

WM_DPICHANGED may fire when the DPI hasn't actually changed. This occurs
during initialization with an interaction from EnableChildWindowDpiMessage.
For maximized windows, this causes the bounds logic to unset WS_MAXIMIZE from
the HWND, which leads to WM_SYSCOMMAND with SC_MAXIMIZE prematurely showing the
window, and short-circuting BrowserView::Show() causing it to skip showing the
contents of the window because the frame is already visible.

BUG=625076
==========

to

==========
Only Update the Scale Factor if the Scale Factor Actually Changed

WM_DPICHANGED may fire when the DPI hasn't actually changed. This occurs
during initialization with an interaction from EnableChildWindowDpiMessage.
For maximized windows, this causes the bounds logic to unset WS_MAXIMIZE from
the HWND, which leads to WM_SYSCOMMAND with SC_MAXIMIZE prematurely showing the
window, and short-circuting BrowserView::Show() causing it to skip showing the
contents of the window because the frame is already visible.

BUG=625076

Committed: https://crrev.com/8e164fb9b1df48c5e01540190a108eaaad86feca
Cr-Commit-Position: refs/heads/master@{#406962}
==========

[commit-bot: I haz the power, 2016-07-21 22:11:10]

Patchset 1 (id:??) landed as
https://crrev.com/8e164fb9b1df48c5e01540190a108eaaad86feca
Cr-Commit-Position: refs/heads/master@{#406962}