Run clang-tidy modernize-use-equals-{delete,default} on //base

See the bugs and cxx post for justification and details:
https://groups.google.com/a/chromium.org/forum/#!topic/cxx/RkOHzIK6Tq8

This change was done using clang-tidy as described here:
https://chromium.googlesource.com/chromium/src/+/lkcr/docs/clang_tidy.md

In some cases the the tool leaves behind a string of commas where it
replaced a member initializer list
(https://bugs.llvm.org/show_bug.cgi?id=35051). They were cleaned up with:
  git diff --name-only | \
    xargs sed -E -i 's/(^\s*|\)\s*):[ ,]*= default/\1 = default/'

BUG=778959,778957

Change-Id: I95a3f3dae4796e4a7beb77793a6101f433a2c649
Reviewed-on: https://chromium-review.googlesource.com/789718
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Chris Watkins <watk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#520033}

CrOS-Libchrome-Original-Commit: bb7211cd3762a8545d29b0d5bfebcb94ec4db081

1 files changed, 3 insertions, 6 deletions

diff --git a/base/message_loop/message_loop.cc b/base/message_loop/message_loop.cc
index 9cddbe89ec..2c8899bf05 100644
--- a/base/message_loop/message_loop.cc
+++ b/base/message_loop/message_loop.cc
@@ -71,14 +71,11 @@ std::unique_ptr<MessagePump> ReturnPump(std::unique_ptr<MessagePump> pump) {
 
 //------------------------------------------------------------------------------
 
-MessageLoop::TaskObserver::TaskObserver() {
-}
+MessageLoop::TaskObserver::TaskObserver() = default;
 
-MessageLoop::TaskObserver::~TaskObserver() {
-}
+MessageLoop::TaskObserver::~TaskObserver() = default;
 
-MessageLoop::DestructionObserver::~DestructionObserver() {
-}
+MessageLoop::DestructionObserver::~DestructionObserver() = default;
 
 //------------------------------------------------------------------------------