Added an integration test for kasko hang reports

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index d829ae4141a84a3edfc57772c03e009b8b86bfcc..ddac91d1011caa9b264f1db9b471652cba991ebb 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -482,6 +482,9 @@
       # Enable crash reporting via Kasko.
       'kasko%': 0,
 
+      # Enable hang reports in Kasko. Requires Kasko to be enabled.
+      'kasko_hang_reports%': 0,
+
       # Enable building with LSan (Clang's -fsanitize=leak option).
       # -fsanitize=leak only works with clang, but lsan=1 implies clang=1
       # See https://sites.google.com/a/chromium.org/dev/developers/testing/leaksanitizer
@@ -1189,6 +1192,7 @@
     'use_sanitizer_options%': '<(use_sanitizer_options)',
     'syzyasan%': '<(syzyasan)',
     'kasko%': '<(kasko)',
+    'kasko_hang_reports%': '<(kasko_hang_reports)',
     'syzygy_optimize%': '<(syzygy_optimize)',
     'lsan%': '<(lsan)',
     'msan%': '<(msan)',
@@ -2896,6 +2900,13 @@
         'include_dirs': [
           '<(DEPTH)/third_party/kasko/include',
         ],
+        'conditions': [
+          ['kasko_hang_reports==1', {
+            'defines': [
+              'KASKO_HANG_REPORTS',
+            ],
+          }],
+        ],
       }],
       ['OS=="win"', {
         'defines': [