focus is_3x3() in SkColorSpace.cpp

There's no need to test approximate equality for the outer
row and column; they really should be exactly 0 or 1.

Replace the post-facto are-we-equal assert with the simpler
is-the-input-3x3.  That's really all I was going for there.
The assert predated is_3x3().

Bug: chromium:897427
Change-Id: I1b36c0e288cbdd30c1dabf8948fae441730d01cf
Reviewed-on: https://skia-review.googlesource.com/c/164183
Commit-Queue: Mike Klein <mtklein@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
1 file changed