[clang-format] tweaked another case of lambda formatting

Summary:
This is done in order to improve cases where the lambda's body is moved too far to the right. Consider the following snippet with column limit set to 79:

```
void f() {
  leader::MakeThisCallHere(&leader_service_,
                           cq_.get(),
                           [this, liveness](const leader::ReadRecordReq& req,
                                            std::function<void()> done) {
                             logger_->HandleReadRecord(
                                 req, resp, std::move(done));
                           });

  leader::MakeAnother(&leader_service_,
                      cq_.get(),
                      [this, liveness](const leader::ReadRecordReq& req,
                                       std::function<void()> done) {
                        logger_->HandleReadRecord(
                            req, resp, std::move(done), a);
                      });
}
```

The tool favors extra indentation for the lambda body and so the code incurs extra wrapping and adjacent calls are indented to a different level. I find this behavior annoying and I'd like the tool to favor new lines and, thus, use the extra width.

The fix, reduced, brings the following formatting.

Before:

    function(1,
             [] {
               DoStuff();
               //
             },
             1);

After:

    function(
        1,
        [] {
          DoStuff();
          //
        },
        1);

Refer to the new tests in FormatTest.cpp

Contributed by oleg.smolsky!

Reviewers: djasper, klimek, krasimir

Subscribers: cfe-commits, owenpan

Tags: #clang

Differential Revision: https://reviews.llvm.org/D52676

llvm-svn: 345753
diff --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp
index 76b495f4..6b6a9af 100644
--- a/clang/lib/Format/UnwrappedLineFormatter.cpp
+++ b/clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -988,8 +988,7 @@
       Path.push_front(Best);
       Best = Best->Previous;
     }
-    for (std::deque<StateNode *>::iterator I = Path.begin(), E = Path.end();
-         I != E; ++I) {
+    for (auto I = Path.begin(), E = Path.end(); I != E; ++I) {
       unsigned Penalty = 0;
       formatChildren(State, (*I)->NewLine, /*DryRun=*/false, Penalty);
       Penalty += Indenter->addTokenToState(State, (*I)->NewLine, false);
@@ -998,8 +997,8 @@
         printLineState((*I)->Previous->State);
         if ((*I)->NewLine) {
           llvm::dbgs() << "Penalty for placing "
-                       << (*I)->Previous->State.NextToken->Tok.getName() << ": "
-                       << Penalty << "\n";
+                       << (*I)->Previous->State.NextToken->Tok.getName()
+                       << " on a new line: " << Penalty << "\n";
         }
       });
     }