Make XFA Caret become immediately visible when moved.

The timer resets when it moves, and the current starting state is
not visible, so moving the caret around using keyboard keys,
typing, the mouse, or switching focus has a 0.6s delay in showing
its position.

This change makes the form feel much more responsive.

Change-Id: Iff38ade9be26d4c5283ee1268b3e2c307182738c
Reviewed-on: https://pdfium-review.googlesource.com/31293
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
diff --git a/xfa/fwl/cfwl_caret.cpp b/xfa/fwl/cfwl_caret.cpp
index c864b2d..666ba82 100644
--- a/xfa/fwl/cfwl_caret.cpp
+++ b/xfa/fwl/cfwl_caret.cpp
@@ -65,6 +65,7 @@
 
   m_pTimerInfo = m_pTimer->StartTimer(kBlinkPeriodMs, true);
   RemoveStates(FWL_WGTSTATE_Invisible);
+  SetStates(kStateHighlight);
 }
 
 void CFWL_Caret::HideCaret() {