Selective build clobbering feature (landmines.py and android build scripts).

build/android/buildbot/buildbot_functions.sh

 #!/bin/bash
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 #
 # Bash functions used by buildbot annotator scripts for the android
 # build of chromium.  Executing this script should not perform actions
 # other than setting variables and defining of functions.
 
 # Number of jobs on the compile line; e.g.  make -j"${JOBS}"
@@ skipping 29 matching lines @@
 # Basic setup for all bots to run after a source tree checkout.
 # Args:
 #   $1: source root.
 #   $2 and beyond: key value pairs which are parsed by bb_parse_args.
 function bb_baseline_setup {
   SRC_ROOT="$1"
   # Remove SRC_ROOT param
   shift
   cd $SRC_ROOT
 
-  if [[ $BUILDBOT_CLOBBER ]]; then
+  echo "@@@BUILD_STEP Parse args@@@"
+  bb_parse_args "$@"
+
+  local out_path="${SRC_ROOT}/out/${BUILDTYPE}"
+  local trigger_path="$out_path/.landmines_triggered"
+
+  if [[ $BUILDBOT_CLOBBER || -f "$trigger_path" ]]; then
     echo "@@@BUILD_STEP Clobber@@@"
+
+    if [[ -f "$trigger_path" ]]; then
+      echo "Clobbering due to triggered landmines: "
+      cat "$trigger_path"
+    fi
+
     # Sdk key expires, delete android folder.
     # crbug.com/145860
     rm -rf ~/.android
-    rm -rf "${SRC_ROOT}"/out
-    if [ -e "${SRC_ROOT}"/out ] ; then
-      echo "Clobber appeared to fail?  ${SRC_ROOT}/out still exists."
+    rm -rf "$out_path"
+    if [ -e "$out_path" ] ; then
+      echo "Clobber appeared to fail?  $out_path still exists."
       echo "@@@STEP_WARNINGS@@@"
     fi
   fi
 
   echo "@@@BUILD_STEP Environment setup@@@"
-  bb_parse_args "$@"
 
   local BUILDTOOL=$(bb_get_json_prop "$FACTORY_PROPERTIES" buildtool)
   if [[ $BUILDTOOL = ninja ]]; then
     export GYP_GENERATORS=ninja
   fi
   export GOMA_DIR=/b/build/goma
   . build/android/envsetup.sh
   adb kill-server
 }
 
@@ skipping 225 matching lines @@
   )
 }
 
 # Retrieve a packed json property using python
 function bb_get_json_prop {
   local JSON="$1"
   local PROP="$2"
 
   python -c "import json; print json.loads('$JSON').get('$PROP', '')"
 }