DevTools: fix rounding of scale in device mode

DevTools: fix rounding of scale in device mode

While resizing the DevTools viewport to be smaller than the emulated device's
screen size in responsive mode, _calculateAndEmulate() clamps the emulated
screen size to preferredScaledWidth/Height(). The condition to do so checks
whether the screen's dimensions are greater than the preferred-scaled
dimensions. The sharp scale calculator in calculateFitScale() would find a scale
nearby the precise value that would result in integer screen sizes.

However, it was possible for the sharp scale to be greater than the actual
scale, which resulted in a smaller preferredScaledWidth/Height() than was
available. This edge case triggers the clamping condition, which led to
inaccurate widths/heights that differed from user input.

BUG=651123
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2449763002
Cr-Commit-Position: refs/heads/master@{#427583}
(cherry picked from commit 2f5985ecef25664e1b6bba43b338683dd5d63c64)

[luoe, 2016-10-27 22:56:18]

luoe@chromium.org changed reviewers:
+ dgozman@chromium.org

[luoe, 2016-10-27 22:56:19]

This CL is to merge a change from ToT to 2883.  Since I do not have committer
status, it still needs an l g t m.  Please take a look.

[luoe, 2016-10-27 22:56:56]

Description was changed from

==========
DevTools: fix rounding of scale in device mode

While resizing the DevTools viewport to be smaller than the emulated device's
screen size in responsive mode, _calculateAndEmulate() clamps the emulated
screen size to preferredScaledWidth/Height(). The condition to do so checks
whether the screen's dimensions are greater than the preferred-scaled
dimensions. The sharp scale calculator in calculateFitScale() would find a scale
nearby the precise value that would result in integer screen sizes.

However, it was possible for the sharp scale to be greater than the actual
scale, which resulted in a smaller preferredScaledWidth/Height() than was
available. This edge case triggers the clamping condition, which led to
inaccurate widths/heights that differed from user input.

BUG=651123

Review-Url: https://codereview.chromium.org/2449763002
Cr-Commit-Position: refs/heads/master@{#427583}
(cherry picked from commit 2f5985ecef25664e1b6bba43b338683dd5d63c64)
==========

to

==========
DevTools: fix rounding of scale in device mode

While resizing the DevTools viewport to be smaller than the emulated device's
screen size in responsive mode, _calculateAndEmulate() clamps the emulated
screen size to preferredScaledWidth/Height(). The condition to do so checks
whether the screen's dimensions are greater than the preferred-scaled
dimensions. The sharp scale calculator in calculateFitScale() would find a scale
nearby the precise value that would result in integer screen sizes.

However, it was possible for the sharp scale to be greater than the actual
scale, which resulted in a smaller preferredScaledWidth/Height() than was
available. This edge case triggers the clamping condition, which led to
inaccurate widths/heights that differed from user input.

BUG=651123
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2449763002
Cr-Commit-Position: refs/heads/master@{#427583}
(cherry picked from commit 2f5985ecef25664e1b6bba43b338683dd5d63c64)
==========

[dgozman, 2016-10-27 22:57:51]

lgtm

[luoe, 2016-10-27 22:58:12]

The CQ bit was checked by luoe@chromium.org

[commit-bot: I haz the power, 2016-10-27 22:59:16]

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, 2016-10-27 23:01:26]

Description was changed from

==========
DevTools: fix rounding of scale in device mode

While resizing the DevTools viewport to be smaller than the emulated device's
screen size in responsive mode, _calculateAndEmulate() clamps the emulated
screen size to preferredScaledWidth/Height(). The condition to do so checks
whether the screen's dimensions are greater than the preferred-scaled
dimensions. The sharp scale calculator in calculateFitScale() would find a scale
nearby the precise value that would result in integer screen sizes.

However, it was possible for the sharp scale to be greater than the actual
scale, which resulted in a smaller preferredScaledWidth/Height() than was
available. This edge case triggers the clamping condition, which led to
inaccurate widths/heights that differed from user input.

BUG=651123
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2449763002
Cr-Commit-Position: refs/heads/master@{#427583}
(cherry picked from commit 2f5985ecef25664e1b6bba43b338683dd5d63c64)
==========

to

==========
DevTools: fix rounding of scale in device mode

While resizing the DevTools viewport to be smaller than the emulated device's
screen size in responsive mode, _calculateAndEmulate() clamps the emulated
screen size to preferredScaledWidth/Height(). The condition to do so checks
whether the screen's dimensions are greater than the preferred-scaled
dimensions. The sharp scale calculator in calculateFitScale() would find a scale
nearby the precise value that would result in integer screen sizes.

However, it was possible for the sharp scale to be greater than the actual
scale, which resulted in a smaller preferredScaledWidth/Height() than was
available. This edge case triggers the clamping condition, which led to
inaccurate widths/heights that differed from user input.

BUG=651123
NOTRY=true
NOPRESUBMIT=true

Review-Url: https://codereview.chromium.org/2449763002
Cr-Commit-Position: refs/heads/master@{#427583}
(cherry picked from commit 2f5985ecef25664e1b6bba43b338683dd5d63c64)
==========

[commit-bot: I haz the power, 2016-10-27 23:01:26]

Committed patchset #1 (id:1)