Settings::devicePixelRatio doesn't do anything and is confusing

Reviewed by James Robinson.


Settings::devicePixelRatio is yet another piece of state trying to
represent the device scale factor. The canonical place to store this
state is Page::m_deviceScaleFactor. Nothing in WebCore references
Settings::devicePixelRatio anymore, so we can remove it.

* page/Settings.cpp:
* page/Settings.h:


* Shared/WebPreferencesStore.h:
    - Remove boilerplate code for the setting.
* UIProcess/API/qt/qquickwebview.cpp:
    - Change these functions to get and set the real device scale factor.
* WebProcess/WebPage/WebPage.cpp:
    - Use the real device scale factor for the viewport calculation.
    - Remove boilerplate code for the setting.

git-svn-id: 268f45cc-cd09-0410-ab3c-d52691b4dbfc
7 files changed