Add stubs for switch and case output

BUG=angle:921

Change-Id: I58bd645a8d53ef5bad9b680e54c8948d50932fca
Reviewed-on: https://chromium-review.googlesource.com/251525
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Tested-by: Olli Etuaho <oetuaho@nvidia.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/compiler/translator/OutputGLSLBase.h b/src/compiler/translator/OutputGLSLBase.h
index d60283a..eb5c582 100644
--- a/src/compiler/translator/OutputGLSLBase.h
+++ b/src/compiler/translator/OutputGLSLBase.h
@@ -37,6 +37,8 @@
     virtual bool visitBinary(Visit visit, TIntermBinary *node);
     virtual bool visitUnary(Visit visit, TIntermUnary *node);
     virtual bool visitSelection(Visit visit, TIntermSelection *node);
+    virtual bool visitSwitch(Visit visit, TIntermSwitch *node);
+    virtual bool visitCase(Visit visit, TIntermCase *node);
     virtual bool visitAggregate(Visit visit, TIntermAggregate *node);
     virtual bool visitLoop(Visit visit, TIntermLoop *node);
     virtual bool visitBranch(Visit visit, TIntermBranch *node);