Work on getting things built with -Wimplicit-fallthrough. This CL was uploaded by git cl split.

Bug: 177475
R=boliu@chromium.org

Change-Id: I31d7cd6f12d989557283bf3d5004f5310aa813bb
Reviewed-on: https://chromium-review.googlesource.com/889798
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Bo <boliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532102}

content/browser/browser_child_process_host_impl.cc

@@ -439,6 +439,7 @@ void BrowserChildProcessHostImpl::OnChildDisconnected() {
         UMA_HISTOGRAM_ENUMERATION("ChildProcess.DisconnectedAlive2",
                                   static_cast<ProcessType>(data_.process_type),
                                   PROCESS_TYPE_MAX);
+        break;
       }
       default:
         break;

content/browser/frame_host/navigation_handle_impl.cc

@@ -894,7 +894,8 @@ NavigationHandleImpl::CheckWillStartRequest() {
         continue;
 
       case NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE:
-        frame_tree_node_->SetCollapsed(true);  // Fall through.
+        frame_tree_node_->SetCollapsed(true);
+        FALLTHROUGH;
       case NavigationThrottle::BLOCK_REQUEST:
       case NavigationThrottle::CANCEL:
       case NavigationThrottle::CANCEL_AND_IGNORE:
@@ -941,7 +942,8 @@ NavigationHandleImpl::CheckWillRedirectRequest() {
         continue;
 
       case NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE:
-        frame_tree_node_->SetCollapsed(true);  // Fall through.
+        frame_tree_node_->SetCollapsed(true);
+        FALLTHROUGH;
       case NavigationThrottle::BLOCK_REQUEST:
       case NavigationThrottle::CANCEL:
       case NavigationThrottle::CANCEL_AND_IGNORE: