Remove requestedStyle from SkTypefaceCache.

The typeface cache contains typefaces which can be compared against to
determine if an already known typeface will work instead of creating a
new typeface id. This is primarily for sharing scaler contexts. How that
typeface was requested is not relevant to this comparison, so don't cache
it. Request caching must be handled separately.

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Review URL: https://codereview.chromium.org/1879423002
8 files changed