initialize fPhase

Found by a GCC warning that

   fPhase = that.fPhase;   // line 193

was sometimes copying over uninitialized data.

Seems pretty harmless to initialize.

Change-Id: I9011ccf965bea4a702e0cca61f89e0aa644c55a6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/227122
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
1 file changed