Pass FLUTTER_TOOL_ARGS to snapshot command. (#29938)

bin/flutter

@@ -121,7 +121,7 @@ function upgrade_flutter () {
 
     retry_upgrade
 
-    "$DART" --snapshot="$SNAPSHOT_PATH" --snapshot-kind=app-jit --packages="$FLUTTER_TOOLS_DIR/.packages" "$SCRIPT_PATH" training
+    "$DART" $FLUTTER_TOOL_ARGS --snapshot="$SNAPSHOT_PATH" --snapshot-kind=app-jit --packages="$FLUTTER_TOOLS_DIR/.packages" "$SCRIPT_PATH" training
     echo "$revision" > "$STAMP_PATH"
   fi
   # The exit here is duplicitous since the function is run in a subshell,

bin/flutter.bat

@@ -152,7 +152,11 @@ GOTO :after_subroutine
 
     POPD
 
-    "%dart%" --snapshot="%snapshot_path%" --snapshot-kind=app-jit --packages="%flutter_tools_dir%\.packages" "%script_path%"
+    IF "%FLUTTER_TOOL_ARGS%" == "" (
+      "%dart%" --snapshot="%snapshot_path%" --snapshot-kind=app-jit --packages="%flutter_tools_dir%\.packages" "%script_path%"
+    ) else (
+      "%dart%" "%FLUTTER_TOOL_ARGS%" --snapshot="%snapshot_path%" --snapshot-kind=app-jit --packages="%flutter_tools_dir%\.packages" "%script_path%"
+    )
     IF "%ERRORLEVEL%" NEQ "0" (
       ECHO Error: Unable to create dart snapshot for flutter tool.
       SET exit_code=%ERRORLEVEL%

dev/bots/test.dart

@@ -180,16 +180,24 @@ Future<void> _runToolTests() async {
   final bq.BigqueryApi bigqueryApi = await _getBigqueryApi();
   await _runSmokeTests();
 
+  // The flutter_tool will currently be snapshotted without asserts. We need
+  // to force it to be regenerated with them enabled.
+  if (!Platform.isWindows) {
+    File(path.join(flutterRoot, 'bin', 'cache', 'flutter_tools.snapshot')).deleteSync();
+    File(path.join(flutterRoot, 'bin', 'cache', 'flutter_tools.stamp')).deleteSync();
+  }
   if (noUseBuildRunner) {
     await _pubRunTest(
       path.join(flutterRoot, 'packages', 'flutter_tools'),
       tableData: bigqueryApi?.tabledata,
+      enableFlutterToolAsserts: !Platform.isWindows,
     );
   } else {
     await _buildRunnerTest(
       path.join(flutterRoot, 'packages', 'flutter_tools'),
       flutterRoot,
       tableData: bigqueryApi?.tabledata,
+      enableFlutterToolAsserts: !Platform.isWindows,
     );
   }