Pass filename mappings to C++ and Java extractors.

Android builds by default put artifacts into out/ subdirectory of
the source tree, causing the extractor to record their names as
relative. The indexer considers such files as sources, which is wrong.
Fortunately, the extractor can be fed a set of filename rewriting
rules (see build/tools/vnames.json).
Also, undo previous unsuccessful attempt use to absolute path for the
output directory to distinguish between source code and artifacts.

Bug: 141385476
Test: run the build, inspect compilation units of the kzip file
Change-Id: I89ec3aed8fd14f43ea6e0b226d54f643346f6125
diff --git a/vnames.json b/vnames.json
new file mode 100644
index 0000000..7b34c52
--- /dev/null
+++ b/vnames.json
@@ -0,0 +1,18 @@
+[
+  {
+    "pattern": "out/(.*)",
+    "vname": {
+      "corpus": "CORPUS",
+      "root": "out",
+      "path": "@1@"
+    }
+  },
+  {
+    "pattern": "(.*)",
+    "vname": {
+      "corpus": "CORPUS",
+      "path": "@1@"
+    }
+  }
+]
+