mesa/es3.1: Add _mesa_is_gles31 helper

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>

src/mesa/main/context.h

@@ -303,7 +303,7 @@ _mesa_is_gles(const struct gl_context *ctx)
 
 
 /**
- * Checks if the context is for GLES 3.x
+ * Checks if the context is for GLES 3.0 or later
  */
 static inline bool
 _mesa_is_gles3(const struct gl_context *ctx)
@@ -312,6 +312,16 @@ _mesa_is_gles3(const struct gl_context *ctx)
 }
 
 
+/**
+ * Checks if the context is for GLES 3.1 or later
+ */
+static inline bool
+_mesa_is_gles31(const struct gl_context *ctx)
+{
+   return ctx->API == API_OPENGLES2 && ctx->Version >= 31;
+}
+
+
 /**
  * Checks if the context supports geometry shaders.
  */