Remove static initializers in SkCodec

Bug: 768878

Switch const declarations to constexpr where appropriate. Speculative
fix for crbug.com/768878.

Change-Id: I7fc356e623ce7a0f2b87e92e9a8ed95d5c423d79
Reviewed-on: https://skia-review.googlesource.com/54101
Commit-Queue: Leon Scroggins <scroggo@google.com>
Reviewed-by: Chris Blume <cblume@chromium.org>
diff --git a/src/codec/SkBmpRLECodec.cpp b/src/codec/SkBmpRLECodec.cpp
index bd4624e..18c0a79 100644
--- a/src/codec/SkBmpRLECodec.cpp
+++ b/src/codec/SkBmpRLECodec.cpp
@@ -338,10 +338,10 @@
     const int height = dstInfo.height();
 
     // Set RLE flags
-    static const uint8_t RLE_ESCAPE = 0;
-    static const uint8_t RLE_EOL = 0;
-    static const uint8_t RLE_EOF = 1;
-    static const uint8_t RLE_DELTA = 2;
+    constexpr uint8_t RLE_ESCAPE = 0;
+    constexpr uint8_t RLE_EOL = 0;
+    constexpr uint8_t RLE_EOF = 1;
+    constexpr uint8_t RLE_DELTA = 2;
 
     // Destination parameters
     int x = 0;