Fix up all the easy virtual ... SK_OVERRIDE cases.

This fixes every case where virtual and SK_OVERRIDE were on the same line,
which should be the bulk of cases.  We'll have to manually clean up the rest
over time unless I level up in regexes.

for f in (find . -type f); perl -p -i -e 's/virtual (.*)SK_OVERRIDE/\1SK_OVERRIDE/g' $f; end

BUG=skia:

Review URL: https://codereview.chromium.org/806653007
diff --git a/bench/ChecksumBench.cpp b/bench/ChecksumBench.cpp
index 7d3ec9f..661f9e6 100644
--- a/bench/ChecksumBench.cpp
+++ b/bench/ChecksumBench.cpp
@@ -35,7 +35,7 @@
         }
     }
 
-    virtual bool isSuitableFor(Backend backend) SK_OVERRIDE {
+    bool isSuitableFor(Backend backend) SK_OVERRIDE {
         return backend == kNonRendering_Backend;
     }