Remove react-packager indirection.

Summary:
This moves the `src` directory one level up and removes the `react-packager` folder. Personally, I always disliked this indirection. I'm reorganizing some things in RNP, so this seems to make sense.

Not sure if I forgot to update any paths. Can anyone advice if there are more places that need change?

Reviewed By: jeanlauliac

Differential Revision: D4487867

fbshipit-source-id: d63f9c79d6238300df9632d2e6a4e6a4196d5ccb

packager/src/ModuleGraph/node-haste/HasteFS.js

@@ -0,0 +1,80 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @flow
+ */
+
+'use strict';
+
+const {dirname, join, parse} = require('path');
+
+module.exports = class HasteFS {
+  directories: Set<string>;
+  directoryEntries: Map<string, Array<string>>;
+  files: Set<string>;
+
+  constructor(files: Array<string>) {
+    this.directories = buildDirectorySet(files);
+    this.directoryEntries = buildDirectoryEntries(files.map(parse));
+    this.files = new Set(files);
+  }
+
+  closest(path: string, fileName: string): ?string {
+    let {dir, root} = parse(path);
+    do {
+      const candidate = join(dir, fileName);
+      if (this.files.has(candidate)) {
+        return candidate;
+      }
+      dir = dirname(dir);
+    } while (dir !== '.' && dir !== root);
+    return null;
+  }
+
+  dirExists(path: string) {
+    return this.directories.has(path);
+  }
+
+  exists(path: string) {
+    return this.files.has(path);
+  }
+
+  getAllFiles() {
+    return Array.from(this.files.keys());
+  }
+
+  matches(directory: string, pattern: RegExp) {
+    const entries = this.directoryEntries.get(directory);
+    return entries ? entries.filter(pattern.test, pattern) : [];
+  }
+};
+
+function buildDirectorySet(files) {
+  const directories = new Set();
+  files.forEach(path => {
+    let {dir, root} = parse(path);
+    while (dir !== '.' && dir !== root && !directories.has(dir)) {
+      directories.add(dir);
+      dir = dirname(dir);
+    }
+  });
+  return directories;
+}
+
+function buildDirectoryEntries(files) {
+  const directoryEntries = new Map();
+  files.forEach(({base, dir}) => {
+    const entries = directoryEntries.get(dir);
+    if (entries) {
+      entries.push(base);
+    } else {
+      directoryEntries.set(dir, [base]);
+    }
+  });
+  return directoryEntries;
+}