Avoid last param to CTFontCreateWithGraphicsFont.

The last parameter of CTFontCreateWithGraphicsFont (CTFontDescriptorRef
attributes) *must* be nullptr. If non-nullptr then with fonts with
variation axes, the copy will fail in CGFontVariationFromDictCallback
when it assumes kCGFontVariationAxisName is CFNumberRef which it quite
obviously is not.

TBR=reed@google.com
Blocking dev builds, just removes code.

BUG=chromium:535109
Review URL: https://codereview.chromium.org/1362053003

Cherry-pick: 0584631f5254add2f85d94f788d9d6115509211e
Approval: https://crbug.com/524646#c34
1 file changed