Better handle of 0 edge case in duplicate method skipping

Change-Id: Ic701096167e57d8e639a16e4dee8eea2cbb3e0a8
diff --git a/src/compiler.cc b/src/compiler.cc
index cf37d6f..132bf25 100644
--- a/src/compiler.cc
+++ b/src/compiler.cc
@@ -1414,7 +1414,7 @@
     it.Next();
   }
   // Compile direct methods
-  uint32_t previous_direct_method_idx = 0;
+  int64_t previous_direct_method_idx = -1;
   while (it.HasNextDirectMethod()) {
     uint32_t method_idx = it.GetMemberIndex();
     if (method_idx == previous_direct_method_idx) {
@@ -1429,7 +1429,7 @@
     it.Next();
   }
   // Compile virtual methods
-  uint32_t previous_virtual_method_idx = 0;
+  int64_t previous_virtual_method_idx = -1;
   while (it.HasNextVirtualMethod()) {
     uint32_t method_idx = it.GetMemberIndex();
     if (method_idx == previous_virtual_method_idx) {