[wasm] Support validation of asm.js modules with != 3 args.

src/mips/macro-assembler-mips.cc

Index: src/mips/macro-assembler-mips.cc
diff --git a/src/mips/macro-assembler-mips.cc b/src/mips/macro-assembler-mips.cc
index d1e60bd7f468dc1ab0844c472615e55b2126eaf8..302396f8112f09b93b7540392a74ec5f597a2260 100644
--- a/src/mips/macro-assembler-mips.cc
+++ b/src/mips/macro-assembler-mips.cc
@@ -5594,7 +5594,9 @@ void MacroAssembler::CallRuntime(const Runtime::Function* f, int num_arguments,
   // arguments passed in because it is constant. At some point we
   // should remove this need and make the runtime routine entry code
   // smarter.
-  PrepareCEntryArgs(num_arguments);
+  if (num_arguments >= 0) {
+    PrepareCEntryArgs(num_arguments);
+  }
   PrepareCEntryFunction(ExternalReference(f, isolate()));
   CEntryStub stub(isolate(), 1, save_doubles);
   CallStub(&stub, TypeFeedbackId::None(), al, zero_reg, Operand(zero_reg), bd);