Fixes error handling in GetAttachedShaders
TRAC #11846
Signed-off-by: Nicolas Capens
Signed-off-by: Daniel Koch

Author:    Shannon Woods

git-svn-id: https://angleproject.googlecode.com/svn/trunk@139 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/libGLESv2/libGLESv2.cpp b/src/libGLESv2/libGLESv2.cpp
index 9433bb2..6147e86 100644
--- a/src/libGLESv2/libGLESv2.cpp
+++ b/src/libGLESv2/libGLESv2.cpp
@@ -1902,7 +1902,14 @@
 
             if (!programObject)
             {
-                return error(GL_INVALID_VALUE);
+                if (context->getShader(program))
+                {
+                    return error(GL_INVALID_OPERATION);
+                }
+                else
+                {
+                    return error(GL_INVALID_VALUE);
+                }
             }
 
             return programObject->getAttachedShaders(maxcount, count, shaders);