For #21084: put git hash on About screen in release builds.

app/build.gradle

@@ -42,6 +42,7 @@ android {
         testInstrumentationRunnerArguments clearPackageData: 'true'
         resValue "bool", "IS_DEBUG", "false"
         buildConfigField "boolean", "USE_RELEASE_VERSIONING", "false"
+        buildConfigField "String", "GIT_HASH", "\"\"" // see override in release builds for why it's blank.
         // This should be the "public" base URL of AMO.
         buildConfigField "String", "AMO_BASE_URL", "\"https://addons.mozilla.org\""
         buildConfigField "String", "AMO_COLLECTION_NAME", "\"7dfae8669acc4312a65e8ba5553036\""
@@ -82,6 +83,10 @@ android {
         proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
         matchingFallbacks = ['release'] // Use on the "release" build type in dependencies (AARs)
 
+        // Changing the build config can cause files that depend on BuildConfig.java to recompile
+        // so we only set the git hash in release builds to avoid possible recompilation in debug builds.
+        buildConfigField "String", "GIT_HASH", "\"${Config.getGitHash()}\""
+
         if (gradle.hasProperty("localProperties.autosignReleaseWithDebugKey")) {
             signingConfig signingConfigs.debug
         }
@@ -227,6 +232,7 @@ android {
     composeOptions {
         kotlinCompilerExtensionVersion = Versions.androidx_compose
     }
+
 }
 
 // -------------------------------------------------------------------------------------------------

app/src/main/java/org/mozilla/fenix/settings/about/AboutFragment.kt

@@ -98,6 +98,7 @@ class AboutFragment : Fragment(), AboutPageListener {
             val packageInfo =
                 requireContext().packageManager.getPackageInfo(requireContext().packageName, 0)
             val versionCode = PackageInfoCompat.getLongVersionCode(packageInfo).toString()
+            val maybeFenixGitHash = if (BuildConfig.GIT_HASH.isNotBlank()) ", ${BuildConfig.GIT_HASH}" else ""
             val componentsAbbreviation = getString(R.string.components_abbreviation)
             val componentsVersion =
                 mozilla.components.Build.version + ", " + mozilla.components.Build.gitHash
@@ -108,9 +109,10 @@ class AboutFragment : Fragment(), AboutPageListener {
             val appServicesVersion = mozilla.components.Build.applicationServicesVersion
 
             String.format(
-                "%s (Build #%s)\n%s: %s\n%s: %s\n%s: %s",
+                "%s (Build #%s)%s\n%s: %s\n%s: %s\n%s: %s",
                 packageInfo.versionName,
                 versionCode,
+                maybeFenixGitHash,
                 componentsAbbreviation,
                 componentsVersion,
                 maybeGecko,

app/src/main/res/layout/fragment_about.xml

@@ -59,7 +59,7 @@
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintTop_toBottomOf="@id/about_content"
             app:layout_constraintWidth_percent="0.8"
-            tools:text="1.0.x (Build #x)\nAC: 1.0.0\nGV: 69.x-x\nAS: 1.0.0" />
+            tools:text="1.0.x (Build #x), 0d7383fd2\nAC: 1.0.0, 96ae23b628\nGV: 69.x-x\nAS: 1.0.0" />
 
         <TextView
             android:id="@+id/build_date"