feat(ICU): enable ICU extraction even when when in is not used

BREAKING CHANGES:

"{" is used a a delimiter for ICU messages then it could not be used in text nodes.
"{" should be escaped as "{{ '{' }}"

Before:

    <span>some { valid } text</span>

After:

    <span>some { invalid } text<span> <!-- throw parse error -->
    <span>some {{ '{' }} valid } text</span>

modules/@angular/compiler/test/expander_spec.ts

@@ -6,12 +6,13 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {HtmlAttrAst, HtmlElementAst, HtmlTextAst} from '@angular/compiler/src/html_ast';
-import {HtmlParser} from '@angular/compiler/src/html_parser';
-import {ExpansionResult, expandNodes} from '@angular/compiler/src/i18n/expander';
-import {ParseError} from '@angular/compiler/src/parse_util';
-import {humanizeNodes} from '@angular/compiler/test/html_ast_spec_utils';
-import {ddescribe, describe, expect, iit, it} from '@angular/core/testing/testing_internal';
+import {ddescribe, describe, expect, iit, it} from '../../core/testing/testing_internal';
+import {ExpansionResult, expandNodes} from '../src/expander';
+import {HtmlAttrAst, HtmlElementAst, HtmlTextAst} from '../src/html_ast';
+import {HtmlParser} from '../src/html_parser';
+import {ParseError} from '../src/parse_util';
+
+import {humanizeNodes} from './html_ast_spec_utils';
 
 export function main() {
   describe('Expander', () => {

modules/@angular/compiler/test/template_parser_spec.ts

@@ -30,8 +30,6 @@ var MOCK_SCHEMA_REGISTRY = [{
   useValue: new MockSchemaRegistry({'invalidProp': false}, {'mappedAttr': 'mappedProp'})
 }];
 
-let zeConsole = console;
-
 export function main() {
   var ngIf: CompileDirectiveMetadata;
   var parse:
@@ -864,19 +862,18 @@ There is no directive with "exportAs" set to "dirA" ("<div [ERROR ->]#a="dirA"><
         });
 
         it('should report duplicate reference names', () => {
-          
 expect(() => parse('<div #a></div><div #a></div>', []))
 .toThrowError(
-              `Template parse errors:
+          expect(() => parse('<div #a></div><div #a></div>', []))
+              .toThrowError(`Template parse errors:
 Reference "#a" is defined several times ("<div #a></div><div [ERROR ->]#a></div>"): TestComp@0:19`);
 
         });
 
-        


 it(
-            'should not throw error when there is same reference name in different templates',
-            () => {
-              
 expect(() => parse('<div #a><template #a><span>OK</span></template></div>', []))
-                  .not.toThrowError();
+        it('should not throw error when there is same reference name in different templates',
+           () => {
+             expect(() => parse('<div #a><template #a><span>OK</span></template></div>', []))
+                 .not.toThrowError();
 
-            });
+           });
 
         it('should assign references with empty value to components', () => {
           var dirA = CompileDirectiveMetadata.create({
@@ -1506,6 +1503,38 @@ The pipe 'test' could not be found ("[ERROR ->]{{a | test}}"): TestComp@0:0`);
       });
 
     });
+
+    describe('ICU messages', () => {
+      it('should expand plural messages', () => {
+        const shortForm = '{ count, plural, =0 {small} many {big} }';
+        const expandedForm = '<ng-container [ngPlural]="count">' +
+            '<template ngPluralCase="=0">small</template>' +
+            '<template ngPluralCase="many">big</template>' +
+            '</ng-container>';
+
+        expect(humanizeTplAst(parse(shortForm, []))).toEqual(humanizeTplAst(parse(expandedForm, [
+        ])));
+      });
+
+      it('should expand other messages', () => {
+        const shortForm = '{ sex, gender, =f {foo} other {bar} }';
+        const expandedForm = '<ng-container [ngSwitch]="sex">' +
+            '<template ngSwitchCase="=f">foo</template>' +
+            '<template ngSwitchCase="other">bar</template>' +
+            '</ng-container>';
+
+        expect(humanizeTplAst(parse(shortForm, []))).toEqual(humanizeTplAst(parse(expandedForm, [
+        ])));
+      });
+
+      it('should be possible to escape ICU messages', () => {
+        const escapedForm = 'escaped {{ "{" }}  }';
+
+        expect(humanizeTplAst(parse(escapedForm, []))).toEqual([
+          [BoundTextAst, 'escaped {{ "{" }}  }'],
+        ]);
+      });
+    });
   });
 }