[wasm][asm.js] Permit ternary operator in asm.js returns in some cases.

src/asmjs/asm-typer.h

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SRC_ASMJS_ASM_TYPER_H_
 #define SRC_ASMJS_ASM_TYPER_H_
 
 #include <cstdint>
 #include <string>
 #include <unordered_map>
@@ skipping 346 matching lines @@
   enum HeapAccessType { LoadFromHeap, StoreToHeap };
   AsmType* ValidateHeapAccess(Property* heap, HeapAccessType access_type);
   // 6.11 ValidateFloatCoercion
   bool IsCallToFround(Call* call);
   AsmType* ValidateFloatCoercion(Call* call);
 
   // 5.1 ParameterTypeAnnotations
   AsmType* ParameterTypeAnnotations(Variable* parameter,
                                     Expression* annotation);
   // 5.2 ReturnTypeAnnotations
-  AsmType* ReturnTypeAnnotations(ReturnStatement* statement);
+  AsmType* ReturnTypeAnnotations(Expression* ret_expr);
   // 5.4 VariableTypeAnnotations
   // 5.5 GlobalVariableTypeAnnotations
   AsmType* VariableTypeAnnotations(
       Expression* initializer,
       VariableInfo::Mutability global = VariableInfo::kLocal);
   AsmType* ImportExpression(Property* import);
   AsmType* NewHeapView(CallNew* new_heap_view);
 
   Isolate* isolate_;
   Zone* zone_;
@@ skipping 33 matching lines @@
   ZoneVector<Assignment*> function_pointer_tables_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(AsmTyper);
 };
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // SRC_ASMJS_ASM_TYPER_H_