Increase the system_health.memory_mobile timeout from 3h to 4h

The benchmark regularly takes around 2h50m-3h on Android One, and has
been regularly timing out for the past several months on the waterfall.

NOTRY=true
TBR=nednguyen@google.com

Bug: 775242
Change-Id: I2945eef4c12bcf9540c93760c33f54df66dffc9a
Reviewed-on: https://chromium-review.googlesource.com/827605
Commit-Queue: Charlie Andrews <charliea@chromium.org>
Reviewed-by: Charlie Andrews <charliea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#524150}

testing/buildbot/chromium.perf.json

@@ -3790,7 +3790,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": false,
           "io_timeout": 600,
           "upload_test_results": true
@@ -3821,7 +3821,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": true,
           "io_timeout": 600,
           "upload_test_results": true
@@ -8503,7 +8503,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": false,
           "io_timeout": 600,
           "upload_test_results": true
@@ -8534,7 +8534,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": true,
           "io_timeout": 600,
           "upload_test_results": true
@@ -11227,7 +11227,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": false,
           "io_timeout": 600,
           "upload_test_results": true
@@ -15498,7 +15498,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": false,
           "io_timeout": 600,
           "upload_test_results": true
@@ -15529,7 +15529,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": true,
           "io_timeout": 600,
           "upload_test_results": true
@@ -18222,7 +18222,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": false,
           "io_timeout": 600,
           "upload_test_results": true
@@ -22493,7 +22493,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": false,
           "io_timeout": 600,
           "upload_test_results": true
@@ -22524,7 +22524,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": true,
           "io_timeout": 600,
           "upload_test_results": true
@@ -27164,7 +27164,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": false,
           "io_timeout": 600,
           "upload_test_results": true
@@ -27195,7 +27195,7 @@
             }
           ],
           "expiration": 36000,
-          "hard_timeout": 10800,
+          "hard_timeout": 14400,
           "ignore_task_failure": true,
           "io_timeout": 600,
           "upload_test_results": true

tools/perf/core/perf_data_generator.py

@@ -844,7 +844,7 @@ def generate_telemetry_tests(name, tester_config, benchmarks,
 BENCHMARK_SWARMING_TIMEOUTS = {
     'loading.desktop': 14400, # 4 hours (crbug.com/753798)
     'loading.mobile': 16200, # 4.5 hours
-    'system_health.memory_mobile': 10800, # 3 hours
+    'system_health.memory_mobile': 14400, # 4 hours (crbug.com/775242)
     'system_health.memory_desktop': 10800, # 3 hours
 }