Revert of Add a short term solution to fix OSX 10.11 system font rendering problems.

Revert of Add a short term solution to fix OSX 10.11 system font rendering problems. (patchset #2 id:20001 of https://codereview.chromium.org/1284993004/ )

Reason for revert:
Newly added test has been failing since its introduction

http://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=blink_platform_unittests&showExpectations=true&tests=FontFamilyMatcherMacTest.YosemiteFontWeights

Original issue's description:
> Add a short term solution to fix OSX 10.11 system font rendering problems.
> 
> I landed a CL (https://codereview.chromium.org/1276003003/) which fixes system
> font problems on OSX 10.9 and OSX 10.10. The CL also fixed MatchNSFontFamily()
> to correctly return the system font on 10.11, but this causes glyph rendering
> problems. In the short term, I'm adding logic to MatchNSFontFamily() to return
> nil on 10.11, which was the original behavior before I landed that CL.
> 
> BUG=521034
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=200618

TBR=tkent@chromium.org,keishi@chromium.org,erikchen@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=521034
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=200646

[yurys, 2015-08-17 15:41:17]

Created Revert of Add a short term solution to fix OSX 10.11 system font
rendering problems.

[commit-bot: I haz the power, 2015-08-17 15:41:26]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1296243002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1296243002/1

[commit-bot: I haz the power, 2015-08-17 15:41:55]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=200646