first cut at making iOS work

Replace __arm__ with SK_CPU_ARM
add support for iOS simulator and device
fix const warning in iOSSampleApp
update gyp files

https://code.google.com/p/skia/issues/detail?id=900
tracks fixing missing arm assembly
Review URL: https://codereview.appspot.com/6552045

git-svn-id: http://skia.googlecode.com/svn/trunk@5606 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/utils/SkOSFile.cpp b/src/utils/SkOSFile.cpp
index 7c2b024..1fec35a 100644
--- a/src/utils/SkOSFile.cpp
+++ b/src/utils/SkOSFile.cpp
@@ -132,7 +132,7 @@
     return fHandle != (HANDLE)~0 && get_the_file(fHandle, name, dataPtr, getDir);
 }
 
-#elif defined(SK_BUILD_FOR_MAC) || defined(SK_BUILD_FOR_UNIX) || defined(SK_BUILD_FOR_ANDROID)
+#elif defined(SK_BUILD_FOR_MAC) || defined(SK_BUILD_FOR_UNIX) || defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_IOS)
 
 #if 0
 OSStatus FSPathMakeRef (