[csa] Add Unreachable() and use it after throw sites

src/compiler/code-assembler.cc

Index: src/compiler/code-assembler.cc
diff --git a/src/compiler/code-assembler.cc b/src/compiler/code-assembler.cc
index cbaf07f0025469a65fb63b4891236125d55c3bd3..9befe459a5d1950d27ffbbb06b358f24ba52e0dc 100644
--- a/src/compiler/code-assembler.cc
+++ b/src/compiler/code-assembler.cc
@@ -274,6 +274,11 @@ void CodeAssembler::PopAndReturn(Node* pop, Node* value) {
 
 void CodeAssembler::DebugBreak() { raw_assembler()->DebugBreak(); }
 
+void CodeAssembler::Unreachable() {
+  DebugBreak();
+  raw_assembler()->Unreachable();
+}
+
 void CodeAssembler::Comment(const char* format, ...) {
   if (!FLAG_code_comments) return;
   char buffer[4 * KB];