Modify DeviritualizePrototypeMethods to be run under `OptimizeCalls…

…` and leverage that implementation of property/method usage identification.

This is a step towards supporting ES6 in `DevirtualizePrototypeMethods`.

`OptimizeCalls` is also updated to support clearly mapping potential definition sites to definition functions.

Closes #3040

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=224361231

src/com/google/javascript/jscomp/DefaultPassConfig.java

@@ -2429,7 +2429,9 @@ protected FeatureSet featureSet() {
       new PassFactory(PassNames.DEVIRTUALIZE_PROTOTYPE_METHODS, true) {
         @Override
         protected CompilerPass create(AbstractCompiler compiler) {
-          return new DevirtualizePrototypeMethods(compiler);
+          OptimizeCalls passes = new OptimizeCalls(compiler);
+          passes.addPass(new DevirtualizePrototypeMethods(compiler));
+          return passes;
         }
 
         @Override