unify internal and external release into one flow

Summary:
This diff makes updating the internal and external release part of the same flow. The will be changed to:

1. The chronos job is kicked to start a new release
2. That job kicks of `./prepare-release.sh` (see D20304039) which
   1. bumps the version of all packages
   2. generates the changelog
   3. generates a release diff + test instructions for that
   4. generates a diff with snapshot version updates
   5. submit those commits
3. when this is job is completed, the relevant release commits can be checked out and tested.
4. If these job is landed, this will kick off the OSS builds through `release.sh` (as-is). But, this will also generate a diff that updates the flipper pin to the verify same commit (new).

Next steps:
* [ ] update wiki

Code pointers (irrelevant for review):
- Chronos Job entry https://our.intern.facebook.com/intern/diffusion/WWW/browse/master/flib/intern/sandcastle/commands/SandcastleFlipperAutoReleaseCommand.php?lines=85
- Sonar build step: https://our.intern.facebook.com/intern/diffusion/WWW/browse/master/flib/intern/sandcastle/sonar/SandcastleSonarBuildStep.php?lines=84
- Release commit observer: https://our.intern.facebook.com/intern/diffusion/WWW/browse/master/flib/intern/entity/opensource/github/observers/EntOpensourceGitHubCommitBuilderObserver.php?lines=17-48

Reviewed By: passy

Differential Revision: D20283664

fbshipit-source-id: 129ea862bda4721d707f1b6fdd862a937c0ed6d5

scripts/prepare-release.sh

@@ -38,6 +38,7 @@ fi
 
 echo "✨ Making a new release..."
 
+REVISION="$1"
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 SONAR_DIR="$DIR/../"
 FLIPPERKIT_PODSPEC_PATH="$SONAR_DIR/FlipperKit.podspec"
@@ -49,8 +50,22 @@ FLIPPERKIT_VERSION_TAG='flipperkit_version'
 OLD_VERSION_POD_ARG=$(< "$FLIPPER_PODSPEC_PATH" grep "$FLIPPERKIT_VERSION_TAG =" )
 OLD_VERSION="${OLD_VERSION_POD_ARG##* }"
 
-echo "The currently released version is $OLD_VERSION. What should the version of the next release be?"
-read -r VERSION
+# if we got called with a rev argument, we got triggered from our automatic sandcastle job
+if [ "$REVISION" != "" ]; 
+then
+  # In future, bump majors instead of minors?
+  echo "Automatically bumping version to next minor in package.json"
+  npm -C "$SONAR_DIR" version minor
+  VERSION=$(jq -r '.version' "$SONAR_DIR"/package.json)
+else
+  echo "The currently released version is $OLD_VERSION. What should the version of the next release be?"
+  read -r VERSION
+fi
+
+echo "Preparing release $VERSION..."
+
+# Update react-native-flipper to the very same version
+npm -C "$SONAR_DIR"react-native/react-native-flipper version "$VERSION"
 
 # This could be one expression with GNU sed, but I guess we want to support the BSD crap, too.
 SNAPSHOT_MINOR_VERSION=$(echo "$VERSION" | sed -Ee 's/([0-9]+)\.([0-9]+)\.([0-9]+)/\3 + 1/' | bc)
@@ -82,27 +97,37 @@ echo "Bumping version number for android related files..."
 # Update Android related files
 "$SONAR_DIR"/scripts/bump.sh "$VERSION"
 
-#Update Package.json
-echo "Bumping version number in package.json"
-jq '.version = $newVal' --arg newVal "$VERSION" "$SONAR_DIR"/package.json > tmp.$$.json && mv tmp.$$.json "$SONAR_DIR"/package.json
-
-#Update react-native-flipper to the very same version
-jq '.version = $newVal' --arg newVal "$VERSION" "$SONAR_DIR"/react-native/react-native-flipper/package.json > tmp.$$.json && mv tmp.$$.json "$SONAR_DIR"/react-native/react-native-flipper/package.json
-
-#Generate changelog
-"$SONAR_DIR"/scripts/generate-changelog.js
+# Generate changelog
+./generate-changelog.js
 
+# Create commit
 echo "Committing the files..."
 hg addremove
+hg commit -m "$(echo -e "Flipper Release: v${VERSION}\n\n\
+Summary:\nReleasing version $VERSION\n\n\
+Test Plan:\n\
+* Wait until this build is green\n\
+* Find the release id as explained here: https://our.internmc.facebook.com/intern/wiki/Flipper_Internals/Oncall_Runbook/#testing-the-release-vers and run:
+* \`env FLIPPERVERSION=XXXX /Applications/Flipper.app/Contents/MacOS/Flipper\`\n\
+* ...or, alternatively, run \`yarn build --mac && dist/mac/Flipper.app/Contents/MacOS/Flipper\`\n\
+* Perform exploratory tests\n\n\
+Reviewers: flipper\n\n\
+Tags: accept2ship"
+)"
 
-hg commit -m "Flipper Release: v$VERSION"
-
+# Create snapshot commit
 RELEASE_REV="$(hg log -r . --template "{node}\\n")"
 
 echo "Release commit made as $RELEASE_REV, creating new snapshot version $SNAPSHOT_VERSION..."
 "$SONAR_DIR"/scripts/bump.sh --snapshot "$SNAPSHOT_VERSION"
 
-hg commit -m "Flipper Bump: v$SNAPSHOT_VERSION"
+hg commit -m "$(echo -e "Flipper Snapshot Bump: v${SNAPSHOT_VERSION}\n\n\
+Summary:\nReleasing snapshot version $SNAPSHOT_VERSION\n\n\
+Test Plan:\nN/A\n\n\
+Reviewers: flipper\n\n\
+Tags: accept2ship"
+)"
 
+# Submit diffs
 echo "Submitting diffs for review..."
 jf submit -n -r.^::.