build(ngc): run integration test hermetically

This ensures we run in a clean directory, using our real distribution. It finds bugs like @internal
APIs needed to type-check in the offline compiler, as well as problems in package.json.

Also move tsc-wrapped under tools/@angular

tools/@angular/tsc-wrapped/src/symbols.ts

@@ -0,0 +1,36 @@
+import * as ts from 'typescript';
+
+// TOOD: Remove when tools directory is upgraded to support es6 target
+interface Map<K, V> {
+  has(v: V): boolean;
+  set(k: K, v: V): void;
+  get(k: K): V;
+}
+interface MapConstructor {
+  new<K, V>(): Map<K, V>;
+}
+declare var Map: MapConstructor;
+
+var a: Array<number>;
+
+/**
+ * A symbol table of ts.Symbol to a folded value used during expression folding in Evaluator.
+ *
+ * This is a thin wrapper around a Map<> using the first declaration location instead of the symbol
+ * itself as the key. In the TypeScript binder and type checker, mulitple symbols are sometimes
+ * created for a symbol depending on what scope it is in (e.g. export vs. local). Using the
+ * declaration node as the key results in these duplicate symbols being treated as identical.
+ */
+export class Symbols {
+  private map = new Map<ts.Node, any>();
+
+  public has(symbol: ts.Symbol): boolean { return this.map.has(symbol.getDeclarations()[0]); }
+
+  public set(symbol: ts.Symbol, value: any): void {
+    this.map.set(symbol.getDeclarations()[0], value);
+  }
+
+  public get(symbol: ts.Symbol): any { return this.map.get(symbol.getDeclarations()[0]); }
+
+  static empty: Symbols = new Symbols();
+}