Do not build task_queue.cc and include from webrtc_overrides in Chrome.

This is step 2 of the plan below.

The modified plan
1. First land unmodified task_queue.h into webrtc_override in Chrome
2. Modify build files in the webrtc repo to include the task_queue.h and task_queue.cc from webrtc_overrides. This will breaks webrtc Chrome FYI.
3. Combine a roll of webrtc to Chrome and  a the cl in https://codereview.chromium.org/2293913003/ into one  cl.
The combined cl will roll in build files from  2 and  add task_queue.cc in webrtc_overrides and build task_queue_unittest.cc as part of content_unittests to test task_queue.cc in webrtc_overrides.
4... Start using task queues in webrtc........

BUG=webrtc:5687

Review-Url: https://codereview.webrtc.org/2289203002
Cr-Commit-Position: refs/heads/master@{#13983}

webrtc/base/BUILD.gn

@@ -207,31 +207,41 @@ static_library("rtc_task_queue") {
     "sequenced_task_checker.h",
     "sequenced_task_checker_impl.cc",
     "sequenced_task_checker_impl.h",
-    "task_queue.h",
-    "task_queue_posix.h",
   ]
 
-  if (rtc_build_libevent) {
-    deps = [
-      "//base/third_party/libevent",
-    ]
-  }
-
-  if (rtc_enable_libevent) {
+  if (build_with_chromium) {
     sources += [
-      "task_queue_libevent.cc",
-      "task_queue_posix.cc",
+      "../../webrtc_overrides/webrtc/base/task_queue.cc",
+      "../../webrtc_overrides/webrtc/base/task_queue.h",
     ]
-    all_dependent_configs = [ ":enable_libevent_config" ]
+    include_dirs = [ "../../webrtc_overrides" ]
   } else {
-    if (is_mac || is_ios) {
-      sources += [
-        "task_queue_gcd.cc",
-        "task_queue_posix.cc",
+    sources += [
+      "task_queue.h",
+      "task_queue_posix.h",
+    ]
+    if (rtc_build_libevent) {
+      deps = [
+        "//base/third_party/libevent",
       ]
     }
-    if (is_win) {
-      sources += [ "task_queue_win.cc" ]
+
+    if (rtc_enable_libevent) {
+      sources += [
+        "task_queue_libevent.cc",
+        "task_queue_posix.cc",
+      ]
+      all_dependent_configs = [ ":enable_libevent_config" ]
+    } else {
+      if (is_mac || is_ios) {
+        sources += [
+          "task_queue_gcd.cc",
+          "task_queue_posix.cc",
+        ]
+      }
+      if (is_win) {
+        sources += [ "task_queue_win.cc" ]
+      }
     }
   }
 }

webrtc/base/base.gyp

@@ -149,37 +149,52 @@
         'sequenced_task_checker.h',
         'sequenced_task_checker_impl.cc',
         'sequenced_task_checker_impl.h',
-        'task_queue.h',
-        'task_queue_posix.h',
       ],
       'conditions': [
-        ['build_libevent==1', {
-          'dependencies': [
-            '<(DEPTH)/base/third_party/libevent/libevent.gyp:libevent',
+        ['build_with_chromium==1', {
+          'include_dirs': [
+            '../../webrtc_overrides'
           ],
-        }],
-        ['enable_libevent==1', {
-          'sources': [
-            'task_queue_libevent.cc',
-            'task_queue_posix.cc',
+          'sources' : [
+            '../../webrtc_overrides/webrtc/base/task_queue.cc',
+            '../../webrtc_overrides/webrtc/base/task_queue.h',
+          ]
+        } , {
+          # If not build for chromium, use our own implementation.
+          'sources' : [
+            'task_queue.h',
+            'task_queue_posix.h',
           ],
-          'defines': [ 'WEBRTC_BUILD_LIBEVENT' ],
-          'all_dependent_settings': {
-            'defines': [ 'WEBRTC_BUILD_LIBEVENT' ]
-          },
-        }, {
-          # If not libevent, fall back to the other task queues.
           'conditions': [
-            ['OS=="mac" or OS=="ios"', {
-             'sources': [
-               'task_queue_gcd.cc',
-               'task_queue_posix.cc',
-             ],
+            ['build_libevent==1', {
+              'dependencies': [
+                '<(DEPTH)/base/third_party/libevent/libevent.gyp:libevent',
+              ],
             }],
-            ['OS=="win"', {
-              'sources': [ 'task_queue_win.cc' ],
-            }]
-          ],
+            ['enable_libevent==1', {
+              'sources': [
+                'task_queue_libevent.cc',
+                'task_queue_posix.cc',
+              ],
+              'defines': [ 'WEBRTC_BUILD_LIBEVENT' ],
+              'all_dependent_settings': {
+                'defines': [ 'WEBRTC_BUILD_LIBEVENT' ]
+              },
+            }, {
+              # If not libevent, fall back to the other task queues.
+              'conditions': [
+                ['OS=="mac" or OS=="ios"', {
+                 'sources': [
+                   'task_queue_gcd.cc',
+                   'task_queue_posix.cc',
+                 ],
+                }],
+                ['OS=="win"', {
+                  'sources': [ 'task_queue_win.cc' ],
+                }]
+              ],
+            }],
+          ]
         }],
       ],
     },

webrtc/base/task_queue_unittest.cc

@@ -253,9 +253,6 @@ TEST(TaskQueueTest, PostALot) {
 
   EXPECT_GE(tasks_cleaned_up, tasks_executed);
   EXPECT_EQ(kTaskCount, tasks_cleaned_up);
-
-  LOG(INFO) << "tasks executed: " << tasks_executed
-            << ", tasks cleaned up: " << tasks_cleaned_up;
 }
 
 }  // namespace rtc