Fix some nits in fwl code.

Get rid of one more "Imp".

Change-Id: I8e904aa8cc6fb664c84fa81ec95feab22f445d2d
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/91230
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/xfa/fwl/cfwl_datetimepicker.cpp b/xfa/fwl/cfwl_datetimepicker.cpp
index ba00401..f15df41 100644
--- a/xfa/fwl/cfwl_datetimepicker.cpp
+++ b/xfa/fwl/cfwl_datetimepicker.cpp
@@ -18,9 +18,10 @@
 
 namespace {
 
-const int kDateTimePickerHeight = 20;
+constexpr int kDateTimePickerHeight = 20;
 
 }  // namespace
+
 CFWL_DateTimePicker::CFWL_DateTimePicker(CFWL_App* app)
     : CFWL_Widget(app,
                   Properties{0, FWL_STYLEEXT_DTP_ShortDateFormat, 0},
diff --git a/xfa/fwl/cfwl_monthcalendar.h b/xfa/fwl/cfwl_monthcalendar.h
index 0ce018c..4b8ec8f 100644
--- a/xfa/fwl/cfwl_monthcalendar.h
+++ b/xfa/fwl/cfwl_monthcalendar.h
@@ -21,7 +21,7 @@
   CONSTRUCT_VIA_MAKE_GARBAGE_COLLECTED;
   ~CFWL_MonthCalendar() override;
 
-  // FWL_WidgetImp
+  // CFWL_Widget:
   FWL_Type GetClassID() const override;
   CFX_RectF GetAutosizedWidgetRect() override;
   void Update() override;
diff --git a/xfa/fwl/cfwl_notedriver.cpp b/xfa/fwl/cfwl_notedriver.cpp
index a5d7e47..c3ee31e 100644
--- a/xfa/fwl/cfwl_notedriver.cpp
+++ b/xfa/fwl/cfwl_notedriver.cpp
@@ -67,7 +67,7 @@
 
   auto it = m_eventTargets.find(key);
   if (it != m_eventTargets.end())
-    it->second->FlagInvalid();
+    it->second->Invalidate();
 }
 
 void CFWL_NoteDriver::NotifyTargetHide(CFWL_Widget* pNoteTarget) {
diff --git a/xfa/fwl/cfwl_notedriver.h b/xfa/fwl/cfwl_notedriver.h
index 91ba765..0e8fca7 100644
--- a/xfa/fwl/cfwl_notedriver.h
+++ b/xfa/fwl/cfwl_notedriver.h
@@ -45,7 +45,7 @@
     void SetEventSource(CFWL_Widget* pSource);
     bool ProcessEvent(CFWL_Event* pEvent);
     bool IsValid() const { return m_bValid; }
-    void FlagInvalid() { m_bValid = false; }
+    void Invalidate() { m_bValid = false; }
 
    private:
     bool m_bValid = true;