Allow toString capability to be toggled independent of developer mode

src/core/SkShader.cpp

Index: src/core/SkShader.cpp
===================================================================
--- src/core/SkShader.cpp	(revision 13782)
+++ src/core/SkShader.cpp	(working copy)
@@ -179,7 +179,7 @@
     return ::CreateBitmapShader(src, tmx, tmy, NULL);
 }
 
-#ifdef SK_DEVELOPER
+#ifndef SK_IGNORE_TO_STRING
 void SkShader::toString(SkString* str) const {
     if (this->hasLocalMatrix()) {
         str->append(" ");
@@ -309,7 +309,7 @@
     return kColor_GradientType;
 }
 
-#ifdef SK_DEVELOPER
+#ifndef SK_IGNORE_TO_STRING
 void SkColorShader::toString(SkString* str) const {
     str->append("SkColorShader: (");
 
@@ -348,7 +348,7 @@
     SkDEBUGFAIL("should never get called, since setContext() returned false");
 }
 
-#ifdef SK_DEVELOPER
+#ifndef SK_IGNORE_TO_STRING
 void SkEmptyShader::toString(SkString* str) const {
     str->append("SkEmptyShader: (");