ui: add generic icons

Add a new set of basic/generic icons in XAML including warning and info
icons.

Signed-off-by: Matthew John Cheetham <mjcheetham@outlook.com>

Author: mjcheetham

src/shared/Core/UI/Assets/Images.axaml

@@ -3,14 +3,22 @@
     <ResourceDictionary.ThemeDictionaries>
         <ResourceDictionary x:Key="Default">
             <Color x:Key="IconColor">#FF25292F</Color>
-            <SolidColorBrush x:Key="IconBrush" Color="{StaticResource IconColor}"/>
+            <Color x:Key="WarningColor">#FFFF7F27</Color>
+            <SolidColorBrush x:Key="IconBrush" Color="{DynamicResource IconColor}"/>
+            <SolidColorBrush x:Key="WarningBrush" Color="{DynamicResource WarningColor}"/>
         </ResourceDictionary>
         <ResourceDictionary x:Key="Dark">
             <Color x:Key="IconColor">White</Color>
-            <SolidColorBrush x:Key="IconBrush" Color="{StaticResource IconColor}"/>
+            <Color x:Key="WarningColor">#FFFFD40F</Color>
+            <SolidColorBrush x:Key="IconBrush" Color="{DynamicResource IconColor}"/>
+            <SolidColorBrush x:Key="WarningBrush" Color="{DynamicResource WarningColor}"/>
         </ResourceDictionary>
     </ResourceDictionary.ThemeDictionaries>
-
+    <Pen x:Key="WarningPen" Brush="{DynamicResource WarningBrush}" Thickness="2"/>
+    <!--
+        These icon resource keys must be kept in sync with the IconConverter found in
+        src/shared/Core/UI/Converters/IconConverter.cs.
+      -->
     <DrawingImage x:Key="GcmLogo">
         <DrawingImage.Drawing>
             <DrawingGroup>
@@ -50,4 +58,15 @@
             </DrawingGroup>
         </DrawingImage.Drawing>
     </DrawingImage>
+    <DrawingImage x:Key="WarningIcon">
+        <DrawingImage.Drawing>
+            <DrawingGroup>
+                <DrawingGroup.Children>
+                    <GeometryDrawing Pen="{DynamicResource WarningPen}" Geometry="M12,2 L22,20 L2,20 Z"/>
+                    <GeometryDrawing Pen="{DynamicResource WarningPen}" Geometry="M12,8 L12,14"/>
+                    <GeometryDrawing Brush="{DynamicResource WarningBrush}" Geometry="M11,16 a1,1 0 1,0 2,0 a1,1 0 1,0 -2,0"/>
+                </DrawingGroup.Children>
+            </DrawingGroup>
+        </DrawingImage.Drawing>
+    </DrawingImage>
 </ResourceDictionary>