Fix glGetShaderSource conformance
TRAC #11718
Signed-off-by: Daniel Koch

git-svn-id: https://angleproject.googlecode.com/svn/trunk@92 736b8ea6-26fd-11df-bfd4-992fa37f6226
diff --git a/src/libGLESv2/libGLESv2.cpp b/src/libGLESv2/libGLESv2.cpp
index 8deaa9e..ce1a282 100644
--- a/src/libGLESv2/libGLESv2.cpp
+++ b/src/libGLESv2/libGLESv2.cpp
@@ -2171,7 +2171,7 @@
 
             if (!shaderObject)
             {
-                return error(GL_INVALID_VALUE);
+                return error(GL_INVALID_OPERATION);
             }
 
             shaderObject->getSource(bufsize, length, source);
@@ -2916,7 +2916,7 @@
 
             if (!shaderObject)
             {
-                return error(GL_INVALID_VALUE);
+                return error(GL_INVALID_OPERATION);
             }
 
             shaderObject->setSource(count, string, length);