[arm] Share constant pool entries in snapshot.

src/code-stubs.cc

Index: src/code-stubs.cc
diff --git a/src/code-stubs.cc b/src/code-stubs.cc
index 35fb1fe74ef621f757233d942c7bc4e8458e88c7..a70ea8915bac54f873b9126e7dc2e47aad56c059 100644
--- a/src/code-stubs.cc
+++ b/src/code-stubs.cc
@@ -164,6 +164,9 @@ Handle<Code> CodeStub::GetCode() {
 
   {
     HandleScope scope(isolate());
+    // Canonicalize handles, so that we can share constant pool entries pointing
+    // to code targets without dereferencing their handles.
+    CanonicalHandleScope canonical(isolate());
 
     Handle<Code> new_object = GenerateCode();
     new_object->set_stub_key(GetKey());