VM: Share object pool entries for optimized static calls.

runtime/vm/assembler_arm.h

Index: runtime/vm/assembler_arm.h
diff --git a/runtime/vm/assembler_arm.h b/runtime/vm/assembler_arm.h
index 80b888bc62e248afb71a9209927257463713d5f8..b3014fbc0fcdfba863c0eb2ab4783d6f8487c4f5 100644
--- a/runtime/vm/assembler_arm.h
+++ b/runtime/vm/assembler_arm.h
@@ -680,6 +680,11 @@ class Assembler : public ValueObject {
   void BranchLinkPatchable(const StubEntry& stub_entry);
   void BranchLinkPatchable(const Code& code);
 
+  // Emit a call that shares its object pool entries with other calls
+  // that have the same equivalence marker.
+  void BranchLinkWithEquivalence(const StubEntry& stub_entry,
+                                 const Object& equivalence);
+
   // Branch and link to [base + offset]. Call sequence is never patched.
   void BranchLinkOffset(Register base, int32_t offset);