ART: Introduce compiler data type.

Replace most uses of the runtime's Primitive in compiler
with a new class DataType. This prepares for introducing
new types, such as Uint8, that the runtime does not need
to know about.

Test: m test-art-host-gtest
Test: testrunner.py --host
Bug: 23964345
Change-Id: Iec2ad82454eec678fffcd8279a9746b90feb9b0c
diff --git a/compiler/optimizing/nodes_mips.h b/compiler/optimizing/nodes_mips.h
index 8e439d9..80e652e 100644
--- a/compiler/optimizing/nodes_mips.h
+++ b/compiler/optimizing/nodes_mips.h
@@ -24,7 +24,7 @@
  public:
   // Treat the value as an int32_t, but it is really a 32 bit native pointer.
   HMipsComputeBaseMethodAddress()
-      : HExpression(Primitive::kPrimInt, SideEffects::None(), kNoDexPc) {}
+      : HExpression(DataType::Type::kInt32, SideEffects::None(), kNoDexPc) {}
 
   bool CanBeMoved() const OVERRIDE { return true; }