Fix

Author: knopp

.github/workflows/build-and-upload-engine-artifacts.yml

@@ -9320,15 +9320,38 @@ jobs:
           else
             echo "base=https://engine.flutter0.dev" >> $GITHUB_OUTPUT
           fi
+      - name: Set up depot_tools
+        run: |
+          rm -rf "$HOME/depot_tools"
+          for attempt in 1 2 3; do
+            git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git "$HOME/depot_tools" && break
+            rm -rf "$HOME/depot_tools"
+            echo "depot_tools clone failed (attempt $attempt), retrying..."
+            sleep 5
+          done
+          test -d "$HOME/depot_tools/.git"
+          # Append depot_tools to the PATH for subsequent steps
+          echo "$HOME/depot_tools" >> $GITHUB_PATH
+      # TEMP(build-from-scratch): the engine_tool workspace resolves packages
+      # via path dependencies inside flutter/third_party/dart, which a plain
+      # checkout does not contain. Sync with the slim gclient config (the same
+      # flavor the artifact test jobs use) to materialize them before running
+      # the stamp.
+      - name: Copy gclient file
+        run: |
+          cp engine/scripts/slim.gclient .gclient
+      - name: GClient sync
+        run: |
+          gclient sync -D --no-history --shallow --with_branch_heads
       - name: Generate engine_stamp.json with the deployed Dart SDK
         env:
           FLUTTER_STORAGE_BASE_URL: ${{ steps.storage.outputs.base }}
           FLUTTER_PREBUILT_ENGINE_VERSION: ${{ steps.engine_content_hash.outputs.value }}
         run: |
           cd engine/src
-          # TEMP(build-from-scratch): the engine_tool package is not
-          # pre-resolved without gclient sync, so resolve it explicitly with
-          # the deployed Dart SDK before invoking the tool.
+          # TEMP(build-from-scratch): belt and braces - resolve the remaining
+          # packages with the deployed Dart SDK in case the sync hook did not
+          # prepare the engine_tool .dart_tool.
           ../../bin/dart pub get --directory flutter/tools/engine_tool
           ../../bin/dart flutter/tools/engine_tool/bin/et.dart stamp
       - name: Select the R2 target