[asmjs] Validator should reject modules with repeated functions.

test/cctest/test-asm-validator.cc

Index: test/cctest/test-asm-validator.cc
diff --git a/test/cctest/test-asm-validator.cc b/test/cctest/test-asm-validator.cc
index a07eecf2760644d9309eaf7034583bb1c3d4b2ac..39d490e7a931761924ac310a62635d51145383b2 100644
--- a/test/cctest/test-asm-validator.cc
+++ b/test/cctest/test-asm-validator.cc
@@ -1361,6 +1361,12 @@ TEST(CompareMismatchInt32Float32) {
       "asm: line 1: left and right side of comparison must match\n");
 }
 
+TEST(FunctionRepeated) {
+  CHECK_FUNC_ERROR(
+      "function foo() { return 0; }\n"
+      "function foo() { return 0; }",
+      "asm: line 2: function repeated in module\n");
+}
 
 TEST(Float64ToInt32) {
   CHECK_FUNC_TYPES_BEGIN(