[Turbofan]: Add integer multiplication with overflow to typed lowering.

src/code-stub-assembler.h

Index: src/code-stub-assembler.h
diff --git a/src/code-stub-assembler.h b/src/code-stub-assembler.h
index 518c3f4fed928af33c6c7d14bc9fd90bf7f78fc0..4d090b83f1823c87cbd18bbb4430dc73c861ca46 100644
--- a/src/code-stub-assembler.h
+++ b/src/code-stub-assembler.h
@@ -82,6 +82,8 @@ class CodeStubAssembler : public compiler::CodeAssembler {
   compiler::Node* SmiMin(compiler::Node* a, compiler::Node* b);
   // Computes a % b for Smi inputs a and b; result is not necessarily a Smi.
   compiler::Node* SmiMod(compiler::Node* a, compiler::Node* b);
+  // Computes a * b for Smi inputs a and b; result is not necessarily a Smi.
+  compiler::Node* SmiMul(compiler::Node* a, compiler::Node* b);
 
   // Allocate an object of the given size.
   compiler::Node* Allocate(compiler::Node* size, AllocationFlags flags = kNone);