Clean up TIntermTraverser usage

Remove default parameters from TIntermTraverser.

Also clean up a few dead function declarations in traversers.

TEST=angle_unittests, angle_end2end_tests
BUG=angleproject:1037

Change-Id: I8d126c6c2d5b53e8b14e23e3d102f204a59323b3
Reviewed-on: https://chromium-review.googlesource.com/275184
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Tested-by: Olli Etuaho <oetuaho@nvidia.com>
diff --git a/src/third_party/compiler/ArrayBoundsClamper.cpp b/src/third_party/compiler/ArrayBoundsClamper.cpp
index 288f552..7c68e82 100644
--- a/src/third_party/compiler/ArrayBoundsClamper.cpp
+++ b/src/third_party/compiler/ArrayBoundsClamper.cpp
@@ -43,7 +43,8 @@
 class ArrayBoundsClamperMarker : public TIntermTraverser {
 public:
     ArrayBoundsClamperMarker()
-        : mNeedsClamp(false)
+        : TIntermTraverser(true, false, false),
+          mNeedsClamp(false)
    {
    }