Fix glass extension on MD for Win 7 and below.

Fix glass extension on MD for Win 7 and below.

This also makes visible (but minor) changes on non-MD (the color of the
innermost pixel of client edge shifts slightly).  This is because we didn't
previously inset the glass enough for the light pixel of edge to be completely
inside the semitransparent client edge region.

This also fixes the glass extension if we were to scale up larger than 200%
somehow.

All of these problems were caused by incorrectly computing the necessary
extension.  The biggest problem was that the code did not account for the
innermost 2 px of glass being a very light and then very dark pixel.  We need to
inset by that amount additionally.

The code also used the wrong mechanism to convert DIPs to pixels, which I think
would have caused bugs on systems with multiple monitors with different DPI.

BUG=614146
TEST=Start Chrome on Win 7 and verify there are no bright or dark lines across the window just above the bottom of the tabstrip.

Committed: https://crrev.com/35ebe25ae437740f33a039fbf84af2855bc2f15b
Cr-Commit-Position: refs/heads/master@{#400316}

[Peter Kasting, 2016-06-10 01:59:14]

Description was changed from

==========
Fix DWM extension

BUG=614146
==========

to

==========
Fix glass extension on MD for Win 7 and below.

This also makes visible (but minor) changes on non-MD (the color of the
innermost pixel of client edge shifts slightly).  This is because we didn't
previously inset the glass enough for the light pixel of edge to be completely
inside the semitransparent client edge region.

This also fixes the glass extension if we were to scale up larger than 200%
somehow.

All of these problems were caused by incorrectly computing the necessary
extension.  The biggest problem was that the code did not account for the
innermost 2 px of glass being a very light and then very dark pixel.  We need to
inset by that amount additionally.

The code also used the wrong mechanism to convert DIPs to pixels, which I think
would have caused bugs on systems with multiple monitors with different DPI.

BUG=614146
TEST=Start Chrome on Win 7 and verify there are no bright or dark lines across
the window just above the bottom of the tabstrip.
==========

[Peter Kasting, 2016-06-10 01:59:14]

pkasting@chromium.org changed reviewers:
+ bsep@chromium.org

[Peter Kasting, 2016-06-10 02:00:09]

Bret, I'm not at my Win 7 machine until some time next week -- can you test this
and verify it does indeed fix the problems on MD without introducing any on
non-MD?

[Bret, 2016-06-10 17:24:26]

On 2016/06/10 02:00:09, Peter Kasting wrote:
> Bret, I'm not at my Win 7 machine until some time next week -- can you test
this
> and verify it does indeed fix the problems on MD without introducing any on
> non-MD?

I'm still working on setting up a Windows 7 after my move, but when I'll test it
when that's done.

[Peter Kasting, 2016-06-16 01:26:47]

I verified on Win 7 that this fixes the MD issues without regressing non-MD. 
Tested scale factors 1 and 2.

Please proceed to review.

[Peter Kasting, 2016-06-16 20:21:25]

pkasting@chromium.org changed reviewers:
+ ben@chromium.org
- bsep@chromium.org

[Peter Kasting, 2016-06-16 20:21:26]

Ben, Bret isn't around today, and you helped me figure this out, want to take a
crack at the review?

https://codereview.chromium.org/2056583002/diff/60001/chrome/browser/ui/views...
File chrome/browser/ui/views/frame/glass_browser_frame_view.cc (right):

https://codereview.chromium.org/2056583002/diff/60001/chrome/browser/ui/views...
chrome/browser/ui/views/frame/glass_browser_frame_view.cc:492: if (!md ||
(base::win::GetVersion() < base::win::VERSION_WIN10)) {
This isn't a visible behavior change, it just turns out we don't need this code
on MD Win 10, which I found while investigating this.

[Ben Goodger (Google), 2016-06-16 22:52:06]

lgtm

[Peter Kasting, 2016-06-16 22:54:16]

The CQ bit was checked by pkasting@chromium.org

[commit-bot: I haz the power, 2016-06-16 22:55:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2056583002/60001

[commit-bot: I haz the power, 2016-06-17 00:39:16]

Description was changed from

==========
Fix glass extension on MD for Win 7 and below.

This also makes visible (but minor) changes on non-MD (the color of the
innermost pixel of client edge shifts slightly).  This is because we didn't
previously inset the glass enough for the light pixel of edge to be completely
inside the semitransparent client edge region.

This also fixes the glass extension if we were to scale up larger than 200%
somehow.

All of these problems were caused by incorrectly computing the necessary
extension.  The biggest problem was that the code did not account for the
innermost 2 px of glass being a very light and then very dark pixel.  We need to
inset by that amount additionally.

The code also used the wrong mechanism to convert DIPs to pixels, which I think
would have caused bugs on systems with multiple monitors with different DPI.

BUG=614146
TEST=Start Chrome on Win 7 and verify there are no bright or dark lines across
the window just above the bottom of the tabstrip.
==========

to

==========
Fix glass extension on MD for Win 7 and below.

This also makes visible (but minor) changes on non-MD (the color of the
innermost pixel of client edge shifts slightly).  This is because we didn't
previously inset the glass enough for the light pixel of edge to be completely
inside the semitransparent client edge region.

This also fixes the glass extension if we were to scale up larger than 200%
somehow.

All of these problems were caused by incorrectly computing the necessary
extension.  The biggest problem was that the code did not account for the
innermost 2 px of glass being a very light and then very dark pixel.  We need to
inset by that amount additionally.

The code also used the wrong mechanism to convert DIPs to pixels, which I think
would have caused bugs on systems with multiple monitors with different DPI.

BUG=614146
TEST=Start Chrome on Win 7 and verify there are no bright or dark lines across
the window just above the bottom of the tabstrip.
==========

[commit-bot: I haz the power, 2016-06-17 00:39:17]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-06-17 00:41:09]

Description was changed from

==========
Fix glass extension on MD for Win 7 and below.

This also makes visible (but minor) changes on non-MD (the color of the
innermost pixel of client edge shifts slightly).  This is because we didn't
previously inset the glass enough for the light pixel of edge to be completely
inside the semitransparent client edge region.

This also fixes the glass extension if we were to scale up larger than 200%
somehow.

All of these problems were caused by incorrectly computing the necessary
extension.  The biggest problem was that the code did not account for the
innermost 2 px of glass being a very light and then very dark pixel.  We need to
inset by that amount additionally.

The code also used the wrong mechanism to convert DIPs to pixels, which I think
would have caused bugs on systems with multiple monitors with different DPI.

BUG=614146
TEST=Start Chrome on Win 7 and verify there are no bright or dark lines across
the window just above the bottom of the tabstrip.
==========

to

==========
Fix glass extension on MD for Win 7 and below.

This also makes visible (but minor) changes on non-MD (the color of the
innermost pixel of client edge shifts slightly).  This is because we didn't
previously inset the glass enough for the light pixel of edge to be completely
inside the semitransparent client edge region.

This also fixes the glass extension if we were to scale up larger than 200%
somehow.

All of these problems were caused by incorrectly computing the necessary
extension.  The biggest problem was that the code did not account for the
innermost 2 px of glass being a very light and then very dark pixel.  We need to
inset by that amount additionally.

The code also used the wrong mechanism to convert DIPs to pixels, which I think
would have caused bugs on systems with multiple monitors with different DPI.

BUG=614146
TEST=Start Chrome on Win 7 and verify there are no bright or dark lines across
the window just above the bottom of the tabstrip.

Committed: https://crrev.com/35ebe25ae437740f33a039fbf84af2855bc2f15b
Cr-Commit-Position: refs/heads/master@{#400316}
==========

[commit-bot: I haz the power, 2016-06-17 00:41:11]

Patchset 4 (id:??) landed as
https://crrev.com/35ebe25ae437740f33a039fbf84af2855bc2f15b
Cr-Commit-Position: refs/heads/master@{#400316}

[Bret, 2016-06-17 20:43:16]

On 2016/06/17 00:41:11, commit-bot: I haz the power wrote:
> Patchset 4 (id:??) landed as
> https://crrev.com/35ebe25ae437740f33a039fbf84af2855bc2f15b
> Cr-Commit-Position: refs/heads/master@{#400316}

retroactive lgtm