Work on getting things built with -Wimplicit-fallthrough. This CL was…

… uploaded by git cl split.

R=jochen@chromium.org

Change-Id: I9bfb6786d2fb2ef764c91145c488b50cbf76c487
Reviewed-on: https://chromium-review.googlesource.com/889879
Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532422}

pdf/pdfium/pdfium_engine.cc

@@ -1405,6 +1405,7 @@ bool PDFiumEngine::HandleEvent(const pp::InputEvent& event) {
       // TODO(dsinclair): This should allow a little bit of movement (up to the
       // touch radii) to account for finger jiggle.
       KillTouchTimer(next_touch_timer_id_);
+      break;
     default:
       break;
   }