add CG imagedecoder (still needs encoding)
update some sample files to not use obsolete SkShaderExtras.h



git-svn-id: http://skia.googlecode.com/svn/trunk@46 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/samplecode/SampleImageDir.cpp b/samplecode/SampleImageDir.cpp
index 2c55ab0..32a719b 100644
--- a/samplecode/SampleImageDir.cpp
+++ b/samplecode/SampleImageDir.cpp
@@ -10,7 +10,7 @@
 #include "SkShader.h"
 #include "SkUtils.h"
 #include "SkXfermode.h"
-#include "SkShaderExtras.h"
+#include "SkComposeShader.h"
 #include "SkColorPriv.h"
 #include "SkColorFilter.h"
 #include "SkTime.h"