ui: Fixed layout of QtBookmarkBrowser

* fixed window size and resizing
* fixed layout and spacing
* removed focus rects on Mac
* fixed filter dropdown style for Mac
* reuse button handling from QtWindow
* use different colors for category and bookmark rows
* allow clicking full row for expansion
* show edit and delete button only on hover
* ellide bookmark name when little space

src/lib_gui/qt/utility/utilityQt.cpp

@@ -28,6 +28,13 @@ namespace utility
 		widget->setAutoFillBackground(true);
 	}
 
+	void setWidgetRetainsSpaceWhenHidden(QWidget* widget)
+	{
+		QSizePolicy pol = widget->sizePolicy();
+		pol.setRetainSizeWhenHidden(true);
+		widget->setSizePolicy(pol);
+	}
+
 	void loadFontsFromDirectory(const std::string& path, const std::string& extension)
 	{
 		std::vector<std::string> extensions;

src/lib_gui/qt/utility/utilityQt.h

@@ -12,6 +12,8 @@ class QWidget;
 namespace utility
 {
 	void setWidgetBackgroundColor(QWidget* widget, const std::string& color);
+	void setWidgetRetainsSpaceWhenHidden(QWidget* widget);
+
 	void loadFontsFromDirectory(const std::string& path, const std::string& extension = ".otf");
 
 	std::string getStyleSheet(const std::string& path);