refactor(compiler): Support ngProjectAs attributes (#51544)

Content project allows the content to specify its own selector for matching against content projection slots, using the `ngProjectAs` special attribute. We can now treat this attribue specially, and generate the appropriate flag in the consts array, followed by the parsed CSS selector.

PR Close #51544

packages/compiler-cli/test/compliance/test_cases/r3_compiler_compliance/components_and_directives/content_projection/TEST_CASES.json

@@ -99,8 +99,7 @@
             "ng_project_as_selector.js"
           ]
         }
-      ],
-      "skipForTemplatePipeline": true
+      ]
     },
     {
       "description": "should take the first selector if multiple values are passed into ngProjectAs",
@@ -114,8 +113,7 @@
             "ng_project_as_compound_selector.js"
           ]
         }
-      ],
-      "skipForTemplatePipeline": true
+      ]
     },
     {
       "description": "should include parsed ngProjectAs selectors into template attrs",
@@ -129,8 +127,7 @@
             "ng_project_as_attribute.js"
           ]
         }
-      ],
-      "skipForTemplatePipeline": true
+      ]
     },
     {
       "description": "should capture the node name of ng-content with a structural directive",