Add an option to support for GL_OES_EGL_image_external.

Comes with this extension is the new sampler type samplerExternalOES.

ANGLEBUG=175
TEST=compile the attached shader file
Review URL: http://codereview.appspot.com/4809076

git-svn-id: https://angleproject.googlecode.com/svn/trunk@728 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/compiler/Initialize.cpp b/src/compiler/Initialize.cpp
index 74a2de3..e0e1db9 100644
--- a/src/compiler/Initialize.cpp
+++ b/src/compiler/Initialize.cpp
@@ -363,6 +363,12 @@
     s.append(TString("vec4 texture2DProjLod(sampler2D sampler, vec4 coord, float lod);"));
     s.append(TString("vec4 textureCubeLod(samplerCube sampler, vec3 coord, float lod);"));
 
+    if (resources.OES_EGL_image_external) {
+        s.append(TString("vec4 texture2D(samplerExternalOES sampler, vec2 coord);"));
+        s.append(TString("vec4 texture2DProj(samplerExternalOES sampler, vec3 coord);"));
+        s.append(TString("vec4 texture2DProj(samplerExternalOES sampler, vec4 coord);"));
+    }
+
     return s;
 }
 
@@ -388,6 +394,12 @@
     s.append(TString("vec4 texture2DProj(sampler2D sampler, vec4 coord, float bias);"));
     s.append(TString("vec4 textureCube(samplerCube sampler, vec3 coord, float bias);"));
 
+    if (resources.OES_EGL_image_external) {
+        s.append(TString("vec4 texture2D(samplerExternalOES sampler, vec2 coord);"));
+        s.append(TString("vec4 texture2DProj(samplerExternalOES sampler, vec3 coord);"));
+        s.append(TString("vec4 texture2DProj(samplerExternalOES sampler, vec4 coord);"));
+    }
+
     if (resources.OES_standard_derivatives) {
         s.append(TString("float dFdx(float p);"));
         s.append(TString("vec2  dFdx(vec2  p);"));
@@ -625,5 +637,7 @@
                            TExtensionBehavior& extBehavior)
 {
     if (resources.OES_standard_derivatives)
-        extBehavior["GL_OES_standard_derivatives"] = EBhDisable;
+        extBehavior["GL_OES_standard_derivatives"] = EBhUndefined;
+    if (resources.OES_EGL_image_external)
+        extBehavior["GL_OES_EGL_image_external"] = EBhUndefined;
 }