build: remove example-module from gitignore

In order to work around an Angular Bazel bug where genfiles aren't
properly picked up in the `ng_module` metadata bundler, we need to
check-in the example module into the source-file and use the
example-module as a real source instead of generating it dynamically
through a genfile. This allows us to temporarily fix the examples package
until the bug (angular/angular#30259) is fixed.

Author: devversion

.gitignore

@@ -7,7 +7,8 @@
 /bazel-out
 
 # Example module file will be auto-generated.
-/src/material-examples/example-module.ts
+# TODO(devversion): re-add the example-module once angular#30259 is fixed.
+# /src/material-examples/example-module.ts
 
 # dependencies
 node_modules
@@ -40,4 +41,4 @@ yarn-error.log
 testem.log
 /.chrome
 /.git
-/.firebase
+/.firebase

src/material-examples/BUILD.bazel

@@ -7,7 +7,8 @@ load("//tools/package-docs-content:index.bzl", "package_docs_content")
 
 ng_module(
   name = "examples",
-  srcs = glob(["**/*.ts"]) + [":example-module"],
+  # TODO(paul): re-add the example-module genfile once angular/angular#30259 is resolved.
+  srcs = glob(["**/*.ts"]),
   module_name = "@angular/material-examples",
   assets = glob(["**/*.html", "**/*.css"]),
   deps = [