Added flagDecoration feature to allow for flexibility in flag design/shape etc

lib/country_code_picker.dart

@@ -74,6 +74,9 @@ class CountryCodePicker extends StatefulWidget {
   /// Set to true if you want to show drop down button
   final bool showDropDownButton;
 
+  /// [BoxDecoration] for the flag image
+  final Decoration flagDecoration;
+
   CountryCodePicker({
     this.onChanged,
     this.onInit,
@@ -92,6 +95,7 @@ class CountryCodePicker extends StatefulWidget {
     this.showFlagDialog,
     this.hideMainText = false,
     this.showFlagMain,
+    this.flagDecoration,
     this.builder,
     this.flagWidth = 32.0,
     this.enabled = true,
@@ -164,8 +168,11 @@ class CountryCodePickerState extends State<CountryCodePicker> {
               Flexible(
                 flex: widget.alignLeft ? 0 : 1,
                 fit: widget.alignLeft ? FlexFit.tight : FlexFit.loose,
-                child: Padding(
-                  padding: widget.alignLeft
+                child: Container(
+                  clipBehavior:
+                      widget.flagDecoration == null ? Clip.none : Clip.hardEdge,
+                  decoration: widget.flagDecoration,
+                  margin: widget.alignLeft
                       ? const EdgeInsets.only(right: 16.0, left: 8.0)
                       : const EdgeInsets.only(right: 16.0),
                   child: Image.asset(
@@ -281,6 +288,7 @@ class CountryCodePickerState extends State<CountryCodePicker> {
               ? widget.showFlagDialog
               : widget.showFlag,
           flagWidth: widget.flagWidth,
+          flagDecoration: widget.flagDecoration,
           size: widget.dialogSize,
           backgroundColor: widget.dialogBackgroundColor,
           barrierColor: widget.barrierColor,

lib/selection_dialog.dart

@@ -12,6 +12,7 @@ class SelectionDialog extends StatefulWidget {
   final WidgetBuilder emptySearchBuilder;
   final bool showFlag;
   final double flagWidth;
+  final Decoration flagDecoration;
   final Size size;
   final bool hideSearch;
   final Icon closeIcon;
@@ -36,6 +37,7 @@ class SelectionDialog extends StatefulWidget {
     this.textStyle,
     this.boxDecoration,
     this.showFlag,
+    this.flagDecoration,
     this.flagWidth = 32,
     this.size,
     this.backgroundColor,
@@ -142,8 +144,11 @@ class _SelectionDialogState extends State<SelectionDialog> {
         children: <Widget>[
           if (widget.showFlag)
             Flexible(
-              child: Padding(
-                padding: const EdgeInsets.only(right: 16.0),
+              child: Container(
+                margin: const EdgeInsets.only(right: 16.0),
+                decoration: widget.flagDecoration,
+                clipBehavior:
+                    widget.flagDecoration == null ? Clip.none : Clip.hardEdge,
                 child: Image.asset(
                   e.flagUri,
                   package: 'country_code_picker',