Bug 1624708 - Make non-native theme keyboard navigable. r=spohl

By painting focus colors. I suspect this was mostly an oversight? But it is the
most obvious issue I always find with this theme.

I followed active > focus > hover, which seems to match what GTK does (and makes
sense, generally).

Differential Revision: https://phabricator.services.mozilla.com/D68088

--HG--
extra : moz-landing-system : lando

widget/nsNativeBasicTheme.cpp

@@ -107,6 +107,7 @@ static void ComputeCheckColors(const EventStates& aState,
   bool isPressed = !isDisabled && aState.HasAllStates(NS_EVENT_STATE_HOVER |
                                                       NS_EVENT_STATE_ACTIVE);
   bool isHovered = !isDisabled && aState.HasState(NS_EVENT_STATE_HOVER);
+  bool isFocused = aState.HasState(NS_EVENT_STATE_FOCUS);
   bool isChecked = aState.HasState(NS_EVENT_STATE_CHECKED);
 
   sRGBColor fillColor = sBackgroundColor;
@@ -130,6 +131,9 @@ static void ComputeCheckColors(const EventStates& aState,
     } else if (isPressed) {
       fillColor = sBackgroundActiveColor;
       borderColor = sBorderHoverColor;
+    } else if (isFocused) {
+      fillColor = sBackgroundActiveColor;
+      borderColor = sBorderFocusColor;
     } else if (isHovered) {
       fillColor = sBackgroundColor;
       borderColor = sBorderHoverColor;
@@ -298,14 +302,25 @@ static void PaintCheckedRadioButton(DrawTarget* aDrawTarget, const Rect& aRect,
   aDrawTarget->Fill(ellipse, ColorPattern(ToDeviceColor(sBackgroundColor)));
 }
 
+static sRGBColor ComputeBorderColor(const EventStates& aState) {
+  bool isDisabled = aState.HasState(NS_EVENT_STATE_DISABLED);
+  bool isHovered = !isDisabled && aState.HasState(NS_EVENT_STATE_HOVER);
+  bool isFocused = aState.HasState(NS_EVENT_STATE_FOCUS);
+  if (isFocused) {
+    return sBorderFocusColor;
+  }
+  if (isHovered) {
+    return sBorderHoverColor;
+  }
+  return sBorderColor;
+}
+
 static void PaintTextField(DrawTarget* aDrawTarget, const Rect& aRect,
                            const EventStates& aState, uint32_t aDpi) {
   bool isDisabled = aState.HasState(NS_EVENT_STATE_DISABLED);
-  bool isHovered = !isDisabled && aState.HasState(NS_EVENT_STATE_HOVER);
-
   const sRGBColor& backgroundColor =
       isDisabled ? sDisabledColor : sBackgroundColor;
-  const sRGBColor& borderColor = isHovered ? sBorderHoverColor : sBorderColor;
+  const sRGBColor borderColor = ComputeBorderColor(aState);
 
   const CSSCoord kRadius = 4.0f;
 
@@ -336,7 +351,7 @@ std::pair<sRGBColor, sRGBColor> ComputeButtonColors(
     return sButtonColor;
   }();
 
-  const sRGBColor& borderColor = isHovered ? sBorderHoverColor : sBorderColor;
+  const sRGBColor borderColor = ComputeBorderColor(aState);
 
   return std::make_pair(backgroundColor, borderColor);
 }