Revert "[pigeon] Add an initial example app (#3761)"

This reverts commit 746750e.

Author: stuartmorgan

.github/dependabot.yml

@@ -477,25 +477,6 @@ updates:
       - dependency-name: "*"
         update-types: ["version-update:semver-minor", "version-update:semver-patch"]
 
-  - package-ecosystem: "gradle"
-    directory: "/packages/pigeon/example/app/android/app"
-    commit-message:
-      prefix: "[pigeon]"
-    schedule:
-      interval: "weekly"
-    open-pull-requests-limit: 10
-    ignore:
-      - dependency-name: "com.android.tools.build:gradle"
-        update-types: ["version-update:semver-minor", "version-update:semver-patch"]
-      - dependency-name: "junit:junit"
-        update-types: ["version-update:semver-minor", "version-update:semver-patch"]
-      - dependency-name: "org.mockito:*"
-        update-types: ["version-update:semver-minor", "version-update:semver-patch"]
-      - dependency-name: "androidx.test:*"
-        update-types: ["version-update:semver-minor", "version-update:semver-patch"]
-      - dependency-name: "org.robolectric:*"
-        update-types: ["version-update:semver-minor", "version-update:semver-patch"]
-
   - package-ecosystem: "gradle"
     directory: "/packages/pigeon/platform_tests/test_plugin/android"
     commit-message:

packages/pigeon/CHANGELOG.md

@@ -1,7 +1,3 @@
-## NEXT
-
-* Adds an example application that uses Pigeon directly, rather than in a plugin.
-
 ## 9.2.4
 
 * [objc] Fixes a warning due to a C++-style function signature in the codec