Revert "Revert "ART: Reduce the instructions generated by packed switch.""

This reverts commit b4c137630fd2226ad07dfd178ab15725374220f1.

The underlying issue was fixed by https://android-review.googlesource.com/188271 .

Bug: 26121945
Change-Id: I58b08eb1a9f0a5c861f8cda93522af64bcf63920
diff --git a/compiler/optimizing/pc_relative_fixups_x86.cc b/compiler/optimizing/pc_relative_fixups_x86.cc
index b383f1e..a385448 100644
--- a/compiler/optimizing/pc_relative_fixups_x86.cc
+++ b/compiler/optimizing/pc_relative_fixups_x86.cc
@@ -15,6 +15,7 @@
  */
 
 #include "pc_relative_fixups_x86.h"
+#include "code_generator_x86.h"
 
 namespace art {
 namespace x86 {
@@ -79,6 +80,10 @@
   }
 
   void VisitPackedSwitch(HPackedSwitch* switch_insn) OVERRIDE {
+    if (switch_insn->GetNumEntries() <=
+        InstructionCodeGeneratorX86::kPackedSwitchJumpTableThreshold) {
+      return;
+    }
     // We need to replace the HPackedSwitch with a HX86PackedSwitch in order to
     // address the constant area.
     InitializePCRelativeBasePointer();