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/ssa_test.cc b/compiler/optimizing/ssa_test.cc
index f69f417..ac998db 100644
--- a/compiler/optimizing/ssa_test.cc
+++ b/compiler/optimizing/ssa_test.cc
@@ -89,7 +89,7 @@
   // Test that phis had their type set.
   for (HBasicBlock* block : graph->GetBlocks()) {
     for (HInstructionIterator it(block->GetPhis()); !it.Done(); it.Advance()) {
-      ASSERT_NE(it.Current()->GetType(), Primitive::kPrimVoid);
+      ASSERT_NE(it.Current()->GetType(), DataType::Type::kVoid);
     }
   }