Don't use SK_ASSERT in header.

src/core/SkImageInfo.cpp

Index: src/core/SkImageInfo.cpp
diff --git a/src/core/SkImageInfo.cpp b/src/core/SkImageInfo.cpp
index 146a3aeed8b0a4a1b04af80f43cb0742e39069db..2bd90d105ed40b7aafc7d219989bd3b0c1cd090b 100644
--- a/src/core/SkImageInfo.cpp
+++ b/src/core/SkImageInfo.cpp
@@ -9,6 +9,23 @@
 #include "SkReadBuffer.h"
 #include "SkWriteBuffer.h"
 
+int SkColorTypeBytesPerPixel(SkColorType ct) {
+    static const uint8_t gSize[] = {
+        0,  // Unknown
+        1,  // Alpha_8
+        2,  // RGB_565
+        2,  // ARGB_4444
+        4,  // RGBA_8888
+        4,  // BGRA_8888
+        1,  // kIndex_8
+    };
+    SK_COMPILE_ASSERT(SK_ARRAY_COUNT(gSize) == (size_t)(kLastEnum_SkColorType + 1),
+                      size_mismatch_with_SkColorType_enum);
+
+    SkASSERT((size_t)ct < SK_ARRAY_COUNT(gSize));
+    return gSize[ct];
+}
+
 static bool profile_type_is_valid(SkColorProfileType profileType) {
     return (profileType >= 0) && (profileType <= kLastEnum_SkColorProfileType);
 }
@@ -21,6 +38,10 @@ static bool color_type_is_valid(SkColorType colorType) {
     return (colorType >= 0) && (colorType <= kLastEnum_SkColorType);
 }
 
+int SkImageInfo::bytesPerPixel() const {
+    return SkColorTypeBytesPerPixel(fColorType);
+}
+
 void SkImageInfo::unflatten(SkReadBuffer& buffer) {
     fWidth = buffer.read32();
     fHeight = buffer.read32();