Revert "Engine Android scenario test: Upload diff failures whenever they exist"

This reverts commit f7941d1ad3f605a586ed1742253065904b7e1617.

Reason for revert: was failing pre-submit with invalid cloud storage path

Original change's description:
> Engine Android scenario test: Upload diff failures whenever they exist
>
> Change-Id: I3bd0e55add17a50e2962d84a79923e174fd14279
> Reviewed-on: https://flutter-review.googlesource.com/c/recipes/+/9040
> Reviewed-by: Christopher Fujino <fujino@google.com>
> Commit-Queue: Emmanuel Garcia <egarciad@google.com>

TBR=godofredoc@google.com,flutter-scoped@luci-project-accounts.iam.gserviceaccount.com,fujino@google.com,egarciad@google.com

Change-Id: Ief45c56346143cf61ebffc4c32630d89ea98cd94
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://flutter-review.googlesource.com/c/recipes/+/9060
Reviewed-by: Christopher Fujino <fujino@google.com>
Commit-Queue: Christopher Fujino <fujino@google.com>
diff --git a/recipes/engine/scenarios.expected/with_failure_upload_0.json b/recipes/engine/scenarios.expected/with_failure_upload_0.json
index 0749b4e..13b0ac7 100644
--- a/recipes/engine/scenarios.expected/with_failure_upload_0.json
+++ b/recipes/engine/scenarios.expected/with_failure_upload_0.json
@@ -1253,70 +1253,23 @@
   },
   {
     "cmd": [],
-    "name": "Killing Processes"
-  },
-  {
-    "cmd": [
-      "pkill",
-      "chrome"
-    ],
-    "name": "Killing Processes.kill chrome",
+    "name": "RECIPE CRASH (Uncaught exception)",
     "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
+      "@@@STEP_EXCEPTION@@@",
+      "The recipe has crashed at point 'Uncaught exception'!",
+      "",
+      "Traceback (most recent call last):",
+      "  File \"RECIPE_REPO[flutter]/recipes/engine/scenarios.py\", line 151, in RunSteps",
+      "    RunAndroidScenarioTests(api)",
+      "  File \"RECIPE_REPO[flutter]/recipes/engine/scenarios.py\", line 118, in RunAndroidScenarioTests",
+      "    raise AssertionError('Diff detected. Please verify the diff failures.')",
+      "AssertionError: Diff detected. Please verify the diff failures."
     ]
   },
   {
-    "cmd": [
-      "pkill",
-      "dart"
-    ],
-    "name": "Killing Processes.kill dart",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "pkill",
-      "flutter"
-    ],
-    "name": "Killing Processes.kill flutter",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "pkill",
-      "java"
-    ],
-    "name": "Killing Processes.kill java",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "pkill",
-      "adb"
-    ],
-    "name": "Killing Processes.kill adb",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "top",
-      "-b",
-      "-n",
-      "3",
-      "-o",
-      "%MEM"
-    ],
-    "name": "OS info (2)"
-  },
-  {
+    "failure": {
+      "humanReason": "Uncaught Exception: AssertionError('Diff detected. Please verify the diff failures.',)"
+    },
     "name": "$result"
   }
 ]
\ No newline at end of file
diff --git a/recipes/engine/scenarios.expected/with_failure_upload_1.json b/recipes/engine/scenarios.expected/with_failure_upload_1.json
index af9334a..d26bc3e 100644
--- a/recipes/engine/scenarios.expected/with_failure_upload_1.json
+++ b/recipes/engine/scenarios.expected/with_failure_upload_1.json
@@ -1318,70 +1318,23 @@
   },
   {
     "cmd": [],
-    "name": "Killing Processes"
-  },
-  {
-    "cmd": [
-      "pkill",
-      "chrome"
-    ],
-    "name": "Killing Processes.kill chrome",
+    "name": "RECIPE CRASH (Uncaught exception)",
     "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
+      "@@@STEP_EXCEPTION@@@",
+      "The recipe has crashed at point 'Uncaught exception'!",
+      "",
+      "Traceback (most recent call last):",
+      "  File \"RECIPE_REPO[flutter]/recipes/engine/scenarios.py\", line 151, in RunSteps",
+      "    RunAndroidScenarioTests(api)",
+      "  File \"RECIPE_REPO[flutter]/recipes/engine/scenarios.py\", line 118, in RunAndroidScenarioTests",
+      "    raise AssertionError('Diff detected. Please verify the diff failures.')",
+      "AssertionError: Diff detected. Please verify the diff failures."
     ]
   },
   {
-    "cmd": [
-      "pkill",
-      "dart"
-    ],
-    "name": "Killing Processes.kill dart",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "pkill",
-      "flutter"
-    ],
-    "name": "Killing Processes.kill flutter",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "pkill",
-      "java"
-    ],
-    "name": "Killing Processes.kill java",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "pkill",
-      "adb"
-    ],
-    "name": "Killing Processes.kill adb",
-    "~followup_annotations": [
-      "@@@STEP_NEST_LEVEL@1@@@"
-    ]
-  },
-  {
-    "cmd": [
-      "top",
-      "-b",
-      "-n",
-      "3",
-      "-o",
-      "%MEM"
-    ],
-    "name": "OS info (2)"
-  },
-  {
+    "failure": {
+      "humanReason": "Uncaught Exception: AssertionError('Diff detected. Please verify the diff failures.',)"
+    },
     "name": "$result"
   }
 ]
\ No newline at end of file
diff --git a/recipes/engine/scenarios.py b/recipes/engine/scenarios.py
index 9cc898c..5318974 100644
--- a/recipes/engine/scenarios.py
+++ b/recipes/engine/scenarios.py
@@ -107,14 +107,15 @@
         ok_ret='all'
     )
     api.step('Kill emulator', ['kill', '-9', emulator_pid])
-    build_failures_dir = scenario_app_tests.join('build', 'reports', 'diff_failures')
-    if api.path.exists(build_failures_dir):
+    build_failures_dir = scenario_app_tests.join('build', 'reports', 'failures')
+    if result.exc_result.retcode != 0 and api.path.exists(build_failures_dir):
       # Upload any diff failures.
       # If there are any, upload them to the cloud bucket.
       api.bucket_util.upload_folder(
           'Upload diff failures', 'src/flutter/testing/scenario_app',
           'build/reports/diff_failures', 'diff_failures.zip'
       )
+      raise AssertionError('Diff detected. Please verify the diff failures.')
 
 
 def RunSteps(api, properties, env_properties):
@@ -158,7 +159,7 @@
 
 def GenTests(api):
   scenario_failures = GetCheckoutPath(api).join(
-      'flutter', 'testing', 'scenario_app', 'build', 'reports', 'diff_failures'
+      'flutter', 'testing', 'scenario_app', 'build', 'reports', 'failures'
   )
   for upload_packages in (True, False):
     yield api.test(
@@ -174,7 +175,7 @@
                 goma_jobs='1024',
                 upload_packages=upload_packages,
             ),
-        ),
+        ), api.path.exists(scenario_failures),
         api.step_data(
             'Start Android emulator (API level 28)',
             stdout=api.raw_io.output_text(
@@ -200,6 +201,7 @@
         # Makes the test fail.
         api.step_data('Scenario App Integration Tests', retcode=1),
         api.path.exists(scenario_failures),
+        api.expect_exception('AssertionError'),
         api.step_data(
             'Start Android emulator (API level 28)',
             stdout=api.raw_io.output_text(