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

gm/blurquickreject.cpp

Index: gm/blurquickreject.cpp
diff --git a/gm/blurquickreject.cpp b/gm/blurquickreject.cpp
index c970458a886d44456efeed8fbfa3e9612abbade8..452cdf7e9100d90bb459606cb8e25bf6736a306e 100644
--- a/gm/blurquickreject.cpp
+++ b/gm/blurquickreject.cpp
@@ -31,8 +31,8 @@ protected:
     }
 
     void onDraw(SkCanvas* canvas) override {
-        static const SkScalar kBlurRadius = SkIntToScalar(20);
-        static const SkScalar kBoxSize = SkIntToScalar(100);
+        constexpr SkScalar kBlurRadius = SkIntToScalar(20);
+        constexpr SkScalar kBoxSize = SkIntToScalar(100);
 
         SkRect clipRect = SkRect::MakeXYWH(0, 0, kBoxSize, kBoxSize);
         SkRect blurRects[] = {
@@ -73,8 +73,8 @@ protected:
     }
 
 private:
-    static const int kWidth = 300;
-    static const int kHeight = 300;
+    static constexpr int kWidth = 300;
+    static constexpr int kHeight = 300;
 
     typedef GM INHERITED;
 };