Use 5x timeout for web tests on debug builds

Timing stats [1][2] show that debug builds are much more than 2~3x
slower than release builds, so the original 3x timeout was too short.
We also have seen more timeouts on debug bots because of that.

[1] One sample of release build timing stats:
(click the "Timing stats" link at the top-right corner)
https://test-results.appspot.com/data/layout_results/linux-blink-rel/36524/blink_web_tests%20%28with%20patch%29/layout-test-results/results.html

[2] One sample of debug build timing stats:
https://test-results.appspot.com/data/layout_results/linux_chromium_dbg_ng/7051/blink_web_tests%20%28with%20patch%29/layout-test-results/results.html

Change-Id: I0eeeecf3547e576046238338246aa6849386166f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2259134Reviewed-by: Dirk Pranke <dpranke@google.com>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#781601}

third_party/blink/tools/blinkpy/web_tests/port/base.py

@@ -383,8 +383,8 @@ class Port(object):
     def timeout_ms(self):
         timeout_ms = self._default_timeout_ms()
         if self.get_option('configuration') == 'Debug':
-            # Debug is usually 2x-3x slower than Release.
-            return 3 * timeout_ms
+            # Debug is about 5x slower than Release.
+            return 5 * timeout_ms
         if self._build_has_dcheck_always_on():
             # Release with DCHECK is also slower than pure Release.
             return 2 * timeout_ms

third_party/blink/tools/blinkpy/web_tests/port/port_testcase.py

@@ -140,7 +140,7 @@ class PortTestCase(LoggingTestCase):
         self.assertEqual(
             self.make_port(options=optparse.Values({'configuration': 'Debug'
                                                     })).timeout_ms(),
-            3 * self.make_port().timeout_ms())
+            5 * self.make_port().timeout_ms())
 
     def make_dcheck_port(self, options):
         host = MockSystemHost(os_name=self.os_name, os_version=self.os_version)
@@ -159,7 +159,7 @@ class PortTestCase(LoggingTestCase):
         self.assertEqual(
             self.make_dcheck_port(options=optparse.Values(
                 {'configuration': 'Debug'})).timeout_ms(),
-            3 * default_timeout_ms)
+            5 * default_timeout_ms)
 
     def test_driver_cmd_line(self):
         port = self.make_port()