a11y tests: add image buttons

testsuite/a11y/buttons.txt

@@ -15,10 +15,58 @@ window1
     <AtkComponent>
     layer: widget
     alpha: 1
+    button9
+      "push button"
+      parent: grid1
+      index: 0
+      name: Close
+      state: enabled focusable sensitive showing visible
+      toolkit: gtk
+      <AtkComponent>
+      layer: widget
+      alpha: 1
+      <AtkImage>
+      image size: 16 x 16
+      image description: (null)
+      <AtkAction>
+      action 0 name: click
+      action 0 description: Clicks the button
+    button8
+      "push button"
+      parent: grid1
+      index: 1
+      name: Find and Replace
+      state: enabled focusable sensitive showing visible
+      toolkit: gtk
+      <AtkComponent>
+      layer: widget
+      alpha: 1
+      <AtkImage>
+      image size: 16 x 16
+      image description: (null)
+      <AtkAction>
+      action 0 name: click
+      action 0 description: Clicks the button
+    button7
+      "push button"
+      parent: grid1
+      index: 2
+      name: Text Button
+      state: enabled focusable sensitive showing visible
+      toolkit: gtk
+      <AtkComponent>
+      layer: widget
+      alpha: 1
+      <AtkImage>
+      image size: -1 x -1
+      image description: (null)
+      <AtkAction>
+      action 0 name: click
+      action 0 description: Clicks the button
     button6
       "toggle button"
       parent: grid1
-      index: 0
+      index: 3
       name: Test switch
       state: enabled focusable sensitive showing visible
       toolkit: gtk
@@ -31,7 +79,7 @@ window1
     button5
       "toggle button"
       parent: grid1
-      index: 1
+      index: 4
       state: checked enabled focusable sensitive showing visible
       toolkit: gtk
       <AtkComponent>
@@ -43,7 +91,7 @@ window1
     button4
       "radio button"
       parent: grid1
-      index: 2
+      index: 5
       name: Hello World!
       member-of: button4
                  button3
@@ -61,7 +109,7 @@ window1
     button3
       "radio button"
       parent: grid1
-      index: 3
+      index: 6
       name: Hello World!
       member-of: button4
                  button3
@@ -79,7 +127,7 @@ window1
     button2
       "check box"
       parent: grid1
-      index: 4
+      index: 7
       name: Hello World!
       state: enabled focusable sensitive showing visible
       toolkit: gtk
@@ -95,7 +143,7 @@ window1
     button1
       "toggle button"
       parent: grid1
-      index: 5
+      index: 8
       name: Hello World!
       state: armed checked enabled focusable sensitive showing visible
       toolkit: gtk