Bug 443609, key usage for scales isn't intuitive, r=neil

toolkit/content/tests/widgets/test_scale.xul

@@ -102,17 +102,19 @@ function testtag_scale_UI(element, testid, horiz, reverse)
 
   element.focus();
 
+  var leftIncrements = horiz && reverse;
+  var upDecrements = !horiz && !reverse;
   synthesizeKeyExpectEvent("VK_LEFT", { }, element, "change", testid + "key left");
-  is(element.value, reverse ? 9 : 5, testid + " key left");
+  is(element.value, leftIncrements ? 9 : 5, testid + " key left");
   synthesizeKeyExpectEvent("VK_RIGHT", { }, element, "change", testid + "key right");
   is(element.value, 7, testid + " key right");
   synthesizeKeyExpectEvent("VK_UP", { }, element, "change", testid + "key up");
-  is(element.value, reverse ? 9 : 5, testid + " key up");
+  is(element.value, upDecrements ? 5 : 9, testid + " key up");
   synthesizeKeyExpectEvent("VK_DOWN", { }, element, "change", testid + "key down");
   is(element.value, 7, testid + " key down");
 
   synthesizeKeyExpectEvent("VK_PAGE_UP", { }, element, "change", testid + "key page up");
-  is(element.value, reverse ? 11 : 3, testid + " key page up");
+  is(element.value, upDecrements ? 3 : 11, testid + " key page up");
   synthesizeKeyExpectEvent("VK_PAGE_DOWN", { }, element, "change", testid + "key page down");
   is(element.value, 7, testid + " key page down");
 

toolkit/content/widgets/scale.xml

@@ -181,35 +181,47 @@
     </implementation>
 
     <handlers>
-      <handler event="keypress" keycode="VK_UP" preventdefault="true">
-        this._userChanged = true;
-        (this.dir == "reverse") ? this.increase() : this.decrease();
-        this._userChanged = false;
-      </handler>
       <handler event="keypress" keycode="VK_LEFT" preventdefault="true">
-        this._userChanged = true;
-        (this.dir == "reverse") ? this.increase() : this.decrease();
-        this._userChanged = false;
-      </handler>
-      <handler event="keypress" keycode="VK_DOWN" preventdefault="true">
-        this._userChanged = true;
-        (this.dir == "reverse") ? this.decrease() : this.increase();
-        this._userChanged = false;
+        <![CDATA[
+          this._userChanged = true;
+          (this.orient != "vertical" && this.dir == "reverse") ? this.increase() : this.decrease();
+          this._userChanged = false;
+        ]]>
       </handler>
       <handler event="keypress" keycode="VK_RIGHT" preventdefault="true">
-        this._userChanged = true;
-        (this.dir == "reverse") ? this.decrease() : this.increase();
-        this._userChanged = false;
+        <![CDATA[
+          this._userChanged = true;
+          (this.orient != "vertical" && this.dir == "reverse") ? this.decrease() : this.increase();
+          this._userChanged = false;
+        ]]>
+      </handler>
+      <handler event="keypress" keycode="VK_UP" preventdefault="true">
+        <![CDATA[
+          this._userChanged = true;
+          (this.orient == "vertical" && this.dir != "reverse") ? this.decrease() : this.increase();
+          this._userChanged = false;
+        ]]>
+      </handler>
+      <handler event="keypress" keycode="VK_DOWN" preventdefault="true">
+        <![CDATA[
+          this._userChanged = true;
+          (this.orient == "vertical" && this.dir != "reverse") ? this.increase() : this.decrease();
+          this._userChanged = false;
+        ]]>
       </handler>
       <handler event="keypress" keycode="VK_PAGE_UP" preventdefault="true">
-        this._userChanged = true;
-        (this.dir == "reverse") ? this.increasePage() : this.decreasePage();
-        this._userChanged = false;
+        <![CDATA[
+          this._userChanged = true;
+          (this.orient == "vertical" && this.dir != "reverse") ? this.decreasePage() : this.increasePage();
+          this._userChanged = false;
+        ]]>
       </handler>
       <handler event="keypress" keycode="VK_PAGE_DOWN" preventdefault="true">
-        this._userChanged = true;
-        (this.dir == "reverse") ? this.decreasePage() : this.increasePage();
-        this._userChanged = false;
+        <![CDATA[
+          this._userChanged = true;
+          (this.orient == "vertical" && this.dir != "reverse") ? this.increasePage() : this.decreasePage();
+          this._userChanged = false;
+        ]]>
       </handler>
       <handler event="keypress" keycode="VK_HOME" preventdefault="true">
         this._userChanged = true;