Replace a lot of 'static const' with 'constexpr' or 'const'.

gm/megalooper.cpp

Index: gm/megalooper.cpp
diff --git a/gm/megalooper.cpp b/gm/megalooper.cpp
index 385c60efb10869a4a0567e0c7e5c4e533661a26e..6f071cb72c2094883ba048bbfb0a82bd31bb2dbf 100644
--- a/gm/megalooper.cpp
+++ b/gm/megalooper.cpp
@@ -68,11 +68,11 @@ protected:
     }
 
 private:
-    static const int kWidth = 800;
-    static const int kHeight = 800;
-    static const int kHalfOuterClipSize = 100;
-    static const int kHalfSquareSize = 50;
-    static const int kOffsetToOutsideClip = kHalfSquareSize + kHalfOuterClipSize + 1;
+    static constexpr int kWidth = 800;
+    static constexpr int kHeight = 800;
+    static constexpr int kHalfOuterClipSize = 100;
+    static constexpr int kHalfSquareSize = 50;
+    static constexpr int kOffsetToOutsideClip = kHalfSquareSize + kHalfOuterClipSize + 1;
 
     static const SkPoint gBlurOffsets[4];
     static const SkColor gColors[4];
@@ -111,7 +111,7 @@ private:
     }
 
     static sk_sp<SkMaskFilter> MakeBlur() {
-        static const SkScalar kBlurSigma = SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(25));
+        const SkScalar kBlurSigma = SkBlurMask::ConvertRadiusToSigma(SkIntToScalar(25));
 
         return SkBlurMaskFilter::Make(kNormal_SkBlurStyle, kBlurSigma,
                                       SkBlurMaskFilter::kHighQuality_BlurFlag);