Improve NaCl support

- Add nacl_make script to build Skia targets for NaCl using gyp
- Add nacl_interface for command-line apps
- Add nacl_sample as front-end for SampleApp
- Add freetype to DEPS
- Various gyp tweaks for NaCl

TODO:
- Implement GL interface
- Implement font host
- Fix plumbing so that SampleApp works properly
Review URL: https://codereview.appspot.com/6671044

git-svn-id: http://skia.googlecode.com/svn/trunk@6245 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/gpu/gl/SkNativeGLContext.h b/include/gpu/gl/SkNativeGLContext.h
index 52118da..93744e7 100644
--- a/include/gpu/gl/SkNativeGLContext.h
+++ b/include/gpu/gl/SkNativeGLContext.h
@@ -12,7 +12,7 @@
 
 #if defined(SK_BUILD_FOR_MAC)
     #include <AGL/agl.h>
-#elif defined(SK_BUILD_FOR_ANDROID)
+#elif defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_NACL)
     #include <GLES2/gl2.h>
     #include <EGL/egl.h>
 #elif defined(SK_BUILD_FOR_UNIX)
@@ -39,6 +39,10 @@
     private:
     #if defined(SK_BUILD_FOR_MAC)
         AGLContext fOldAGLContext;
+    #elif defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_NACL)
+        EGLContext fOldEGLContext;
+        EGLDisplay fOldDisplay;
+        EGLSurface fOldSurface;
     #elif defined(SK_BUILD_FOR_UNIX)
         GLXContext fOldGLXContext;
         Display* fOldDisplay;
@@ -46,10 +50,7 @@
     #elif defined(SK_BUILD_FOR_WIN32)
         HDC fOldHDC;
         HGLRC fOldHGLRC;
-    #elif defined(SK_BUILD_FOR_ANDROID)
-        EGLContext fOldEGLContext;
-        EGLDisplay fOldDisplay;
-        EGLSurface fOldSurface;
+
     #elif defined(SK_BUILD_FOR_IOS)
         void* fEAGLContext;
     #endif
@@ -62,6 +63,10 @@
 private:
 #if defined(SK_BUILD_FOR_MAC)
     AGLContext fContext;
+#elif defined(SK_BUILD_FOR_ANDROID) || defined(SK_BUILD_FOR_NACL)
+    EGLContext fContext;
+    EGLDisplay fDisplay;
+    EGLSurface fSurface;
 #elif defined(SK_BUILD_FOR_UNIX)
     GLXContext fContext;
     Display* fDisplay;
@@ -72,10 +77,6 @@
     HDC fDeviceContext;
     HGLRC fGlRenderContext;
     static ATOM gWC;
-#elif defined(SK_BUILD_FOR_ANDROID)
-    EGLContext fContext;
-    EGLDisplay fDisplay;
-    EGLSurface fSurface;
 #elif defined(SK_BUILD_FOR_IOS)
     void* fEAGLContext;
 #endif