Compute metrics when graphics is updated

Remove the old schedule_redraw_ mechanism that was only useful because
of our synchronous drawing code. Now that actual painting is
scheduled instead of forced, it becomes pointless.

Rename WorkArea::redraw(bool) to scheduleRedraw(bool), to show that
the drawing is not done right away.

In GuiView::updateInset, call scheduleRedraw(true), so that metrics
are correctly computed (this was the whole point of the exercise).

(cherry picked from commit a31d3dc67d)

src/frontends/WorkArea.h

@@ -36,8 +36,8 @@ public:
 	///
 	virtual ~WorkArea() {}
 
-	/// redraw the screen, without using existing pixmap
-	virtual void redraw(bool update_metrics) = 0;
+	/// Update metrics if needed and schedule a paint event
+	virtual void scheduleRedraw(bool update_metrics) = 0;
 
 	/// close this work area.
 	/// Slot for Buffer::closing signal.

src/frontends/WorkAreaManager.cpp

@@ -35,7 +35,7 @@ void WorkAreaManager::remove(WorkArea * wa)
 void WorkAreaManager::redrawAll(bool update_metrics)
 {
 	for (WorkArea * wa : work_areas_)
-		wa->redraw(update_metrics);
+		wa->scheduleRedraw(update_metrics);
 }
 
 

src/frontends/qt4/GuiView.cpp

@@ -4348,7 +4348,7 @@ Buffer const * GuiView::updateInset(Inset const * inset)
 			continue;
 		Buffer const * buffer = &(wa->bufferView().buffer());
 		if (inset_buffer == buffer)
-			wa->scheduleRedraw();
+			wa->scheduleRedraw(true);
 	}
 	return inset_buffer;
 }

src/frontends/qt4/GuiWorkArea.cpp

@@ -237,7 +237,7 @@ SyntheticMouseEvent::SyntheticMouseEvent()
 GuiWorkArea::Private::Private(GuiWorkArea * parent)
 : p(parent), buffer_view_(0), lyx_view_(0),
   caret_(0), caret_visible_(false),
-  need_resize_(false), schedule_redraw_(false), preedit_lines_(1),
+  need_resize_(false), preedit_lines_(1),
   pixel_ratio_(1.0),
   completer_(new GuiCompleter(p, p)), dialog_mode_(false), shell_escape_(false),
   read_only_(false), clean_(true), externally_modified_(false)
@@ -451,7 +451,7 @@ void GuiWorkArea::toggleCaret()
 }
 
 
-void GuiWorkArea::redraw(bool update_metrics)
+void GuiWorkArea::scheduleRedraw(bool update_metrics)
 {
 	if (!isVisible())
 		// No need to redraw in this case.
@@ -632,18 +632,6 @@ void GuiWorkArea::Private::showCaret()
 
 	caret_->update(point.x_, point.y_, h, l_shape, isrtl, completable);
 
-	if (schedule_redraw_) {
-		// This happens when a graphic conversion is finished. As we don't know
-		// the size of the new graphics, it's better the update everything.
-		// We can't use redraw() here because this would trigger a infinite
-		// recursive loop with showCaret().
-		buffer_view_->resize(p->viewport()->width(), p->viewport()->height());
-		p->viewport()->update();
-		updateScrollbar();
-		schedule_redraw_ = false;
-		return;
-	}
-
 	p->viewport()->update(caret_->rect());
 }
 
@@ -1370,12 +1358,6 @@ bool GuiWorkArea::isFullScreen() const
 }
 
 
-void GuiWorkArea::scheduleRedraw()
-{
-	d->schedule_redraw_ = true;
-}
-
-
 bool GuiWorkArea::inDialogMode() const
 {
 	return d->dialog_mode_;
@@ -1788,7 +1770,7 @@ void TabWorkArea::on_currentTabChanged(int i)
 	GuiWorkArea * wa = workArea(i);
 	LASSERT(wa, return);
 	wa->setUpdatesEnabled(true);
-	wa->redraw(true);
+	wa->scheduleRedraw(true);
 	wa->setFocus();
 	///
 	currentWorkAreaChanged(wa);

src/frontends/qt4/GuiWorkArea.h

@@ -60,13 +60,11 @@ public:
 	/// is GuiView in fullscreen mode?
 	bool isFullScreen() const;
 	///
-	void scheduleRedraw();
-	///
 	BufferView & bufferView();
 	///
 	BufferView const & bufferView() const;
 	///
-	void redraw(bool update_metrics);
+	void scheduleRedraw(bool update_metrics);
 
 	/// return true if the key is part of a shortcut
 	bool queryKeySym(KeySymbol const & key, KeyModifier mod) const;

src/frontends/qt4/GuiWorkArea_Private.h

@@ -122,8 +122,6 @@ struct GuiWorkArea::Private
 
 	///
 	bool need_resize_;
-	///
-	bool schedule_redraw_;
 
 	/// the current preedit text of the input method
 	docstring preedit_string_;