Finished off the GLSL compiler's support for parsing shaders using OES_EGL_image_external.

The GLSL to HLSL translator work is not done yet so the extension is disabled in Shader.cpp.
Review URL: https://codereview.appspot.com/5530081

git-svn-id: https://angleproject.googlecode.com/svn/trunk@946 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/compiler/VariableInfo.cpp b/src/compiler/VariableInfo.cpp
index 843f187..1e9486f 100644
--- a/src/compiler/VariableInfo.cpp
+++ b/src/compiler/VariableInfo.cpp
@@ -63,6 +63,7 @@
           }
       case EbtSampler2D: return SH_SAMPLER_2D;
       case EbtSamplerCube: return SH_SAMPLER_CUBE;
+      case EbtSamplerExternalOES: return SH_SAMPLER_EXTERNAL_OES;
       case EbtSampler2DRect: return SH_SAMPLER_2D_RECT_ARB;
       default: UNREACHABLE();
     }