Split Info into SkylarkInfo and NativeInfo.

Prerequisite to implementing shape-declaration and shape-sharing
for declared providers, and cleaning up NativeInfo interface.

RELNOTES: None.
PiperOrigin-RevId: 166057070
diff --git a/src/main/java/com/google/devtools/build/lib/packages/NativeInfo.java b/src/main/java/com/google/devtools/build/lib/packages/NativeInfo.java
new file mode 100644
index 0000000..d52fa87
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/packages/NativeInfo.java
@@ -0,0 +1,54 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.packages;
+
+import com.google.common.collect.ImmutableCollection;
+import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.events.Location;
+import java.util.Map;
+
+/** Base class for native implementations of {@link Info}. */
+// todo(vladmos,dslomov): make abstract once DefaultInfo stops instantiating it.
+public class NativeInfo extends Info {
+  protected final ImmutableMap<String, Object> values;
+
+  @Override
+  public Object getValue(String name) {
+    return values.get(name);
+  }
+
+  @Override
+  public boolean hasKey(String name) {
+    return values.containsKey(name);
+  }
+
+  @Override
+  public ImmutableCollection<String> getKeys() {
+    return values.keySet();
+  }
+
+  public NativeInfo(NativeProvider<?> provider) {
+    super(provider, Location.BUILTIN);
+    this.values = ImmutableMap.of();
+  }
+
+  public NativeInfo(NativeProvider<?> provider, Map<String, Object> values, Location loc) {
+    super(provider, loc);
+    this.values = copyValues(values);
+  }
+
+  public NativeInfo(NativeProvider<?> provider, Map<String, Object> values) {
+    this(provider, values, Location.BUILTIN);
+  }
+}