SkWStream::writeText inlined.

Motivation: This function is used throughout SkPDF.

Note that the compiler can usually inline the result of strlen() for literal strings.

Before:
    out/Release/nanobench -m WStreamWriteText -q
        Timer overhead: 24.2ns
        ! -> high variance, ? -> moderate variance
            micros   	bench
              6.10  	WStreamWriteText	nonrendering

After:
    out/Release/nanobench -m WStreamWriteText -q
        Timer overhead: 23.9ns
        ! -> high variance, ? -> moderate variance
            micros   	bench
              2.51  	WStreamWriteText	nonrendering

PDF runtime change: -0.8% ±0.04%.

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Review URL: https://codereview.chromium.org/1844343004
3 files changed