feat: introduce source maps for templates (#15011)

The main use case for the generated source maps is to give
errors a meaningful context in terms of the original source
that the user wrote.

Related changes that are included in this commit:

* renamed virtual folders used for jit:
  * ng://<module type>/module.ngfactory.js
  * ng://<module type>/<comp type>.ngfactory.js
  * ng://<module type>/<comp type>.html (for inline templates)
* error logging:
  * all errors that happen in templates are logged
    from the place of the nearest element.
  * instead of logging error messages and stacks separately,
    we log the actual error. This is needed so that browsers apply
    source maps to the stack correctly.
  * error type and error is logged as one log entry.

Note that long-stack-trace zone has a bug that 
disables source maps for stack traces,
see https://github.com/angular/zone.js/issues/661.

BREAKING CHANGE:

- DebugNode.source no more returns the source location of a node.  

Closes 14013

packages/compiler/test/output/ts_emitter_spec.ts

@@ -12,7 +12,7 @@ import * as o from '@angular/compiler/src/output/output_ast';
 import {ImportResolver} from '@angular/compiler/src/output/path_util';
 import {TypeScriptEmitter} from '@angular/compiler/src/output/ts_emitter';
 
-import {stripSourceMap} from './abstract_emitter_spec';
+import {stripSourceMapAndNewLine} from './abstract_emitter_spec';
 
 const someModuleUrl = 'somePackage/somePath';
 const anotherModuleUrl = 'somePackage/someOtherPath';
@@ -52,7 +52,7 @@ export function main() {
     function emitStmt(stmt: o.Statement | o.Statement[], exportedVars: string[] = null): string {
       const stmts = Array.isArray(stmt) ? stmt : [stmt];
       const source = emitter.emitStatements(someModuleUrl, stmts, exportedVars || []);
-      return stripSourceMap(source);
+      return stripSourceMapAndNewLine(source);
     }
 
     it('should declare variables', () => {