Move instruction_set_ to CompilerOptions.

Removes CompilerDriver dependency from ImageWriter and
several other classes.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Test: Pixel 2 XL boots.
Test: m test-art-target-gtest
Test: testrunner.py --target --optimizing
Change-Id: I3c5b8ff73732128b9c4fad9405231a216ea72465
diff --git a/compiler/optimizing/code_generator_arm64.cc b/compiler/optimizing/code_generator_arm64.cc
index 85c5659..979a5d4 100644
--- a/compiler/optimizing/code_generator_arm64.cc
+++ b/compiler/optimizing/code_generator_arm64.cc
@@ -1374,7 +1374,6 @@
 }
 
 CodeGeneratorARM64::CodeGeneratorARM64(HGraph* graph,
-                                       const Arm64InstructionSetFeatures& isa_features,
                                        const CompilerOptions& compiler_options,
                                        OptimizingCompilerStats* stats)
     : CodeGenerator(graph,
@@ -1391,7 +1390,6 @@
       instruction_visitor_(graph, this),
       move_resolver_(graph->GetAllocator(), this),
       assembler_(graph->GetAllocator()),
-      isa_features_(isa_features),
       uint32_literals_(std::less<uint32_t>(),
                        graph->GetAllocator()->Adapter(kArenaAllocCodeGenerator)),
       uint64_literals_(std::less<uint64_t>(),
@@ -1729,6 +1727,10 @@
   stream << DRegister(reg);
 }
 
+const Arm64InstructionSetFeatures& CodeGeneratorARM64::GetInstructionSetFeatures() const {
+  return *GetCompilerOptions().GetInstructionSetFeatures()->AsArm64InstructionSetFeatures();
+}
+
 void CodeGeneratorARM64::MoveConstant(CPURegister destination, HConstant* constant) {
   if (constant->IsIntConstant()) {
     __ Mov(Register(destination), constant->AsIntConstant()->GetValue());