[wasm] Do not create TF nodes during verification

src/wasm/ast-decoder.cc

Index: src/wasm/ast-decoder.cc
diff --git a/src/wasm/ast-decoder.cc b/src/wasm/ast-decoder.cc
index 025ccdf1d7bfc0d2c159e511600b0d313cf0fa9b..db881857ab9a51e80add2bbc587fc855d93a9dfd 100644
--- a/src/wasm/ast-decoder.cc
+++ b/src/wasm/ast-decoder.cc
@@ -830,7 +830,9 @@ class WasmFullDecoder : public WasmDecoder {
           case kExprBr: {
             BreakDepthOperand operand(this, pc_);
             if (Validate(pc_, operand, control_)) {
-              BreakTo(operand.depth);
+              if (build()) {

[titzer, 2016/10/10 14:16:41]

I don't think this is right place to fix it; it should be deeper inside of
BreakTo().

+                BreakTo(operand.depth);
+              }
             }
             len = 1 + operand.length;
             EndControl();