Add CLZ instruction to the ARM integrated assembler.

src/DartARM32/assembler_arm.cc

Index: src/DartARM32/assembler_arm.cc
diff --git a/src/DartARM32/assembler_arm.cc b/src/DartARM32/assembler_arm.cc
index e7295e7ea557afa4a62c3a7eb1787535af133c2a..fe2ca8a0a8c2c72a0fbc9fa91abdf75d1c76f3c7 100644
--- a/src/DartARM32/assembler_arm.cc
+++ b/src/DartARM32/assembler_arm.cc
@@ -317,8 +317,8 @@ void Assembler::mvn(Register rd, Operand o, Condition cond) {
 void Assembler::mvns(Register rd, Operand o, Condition cond) {
   EmitType01(cond, o.type(), MVN, 1, R0, rd, o);
 }
-#endif
 
+// Moved to ARM32::AssemblerARM32::clz()
 void Assembler::clz(Register rd, Register rm, Condition cond) {
   ASSERT(rd != kNoRegister);
   ASSERT(rm != kNoRegister);
@@ -332,8 +332,6 @@ void Assembler::clz(Register rd, Register rm, Condition cond) {
   Emit(encoding);
 }
 
-
-#if 0
 // Moved to ARM32::AssemblerARM32::movw()
 void Assembler::movw(Register rd, uint16_t imm16, Condition cond) {
   ASSERT(cond != kNoCondition);