[Win] Unreviewed gardening.

[Win] Unreviewed gardening.

DebugSuffix targets should use our debugsuffix property sheet, and
will therefore build to the proper output location with the proper
suffix tags.

Also, we must use the WebKit_Libraries environment variable, not a set
of relative paths to the property sheets.

* ANGLE.vcxproj/libEGL.vcxproj: Use 'debugsuffix.props' sheet.
* ANGLE.vcxproj/libGLESv2.vcxproj: Ditto.
* ANGLE.vcxproj/preprocessor.vcxproj: Ditto.
* ANGLE.vcxproj/translator_common.vcxproj: Ditto.
* ANGLE.vcxproj/translator_glsl.vcxproj: Ditto.
* ANGLE.vcxproj/translator_hlsl.vcxproj: Ditto.
* ANGLE.vcxproj/libEGLCommon.props: Use $(DebugSuffix) endings.
* ANGLE.vcxproj/libGLESv2Common.props: Ditto.
* ANGLE.vcxproj/translatorCommon.props: Output to 'lib' folder,
not 'bin' folder. These are libraries!

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@172296 268f45cc-cd09-0410-ab3c-d52691b4dbfc