Bug 1530193 - followup: Fix default type and value of browser.display.focus_ring_style.

It warns on debug builds.

layout/base/nsPresContext.cpp

@@ -171,7 +171,6 @@ nsPresContext::nsPresContext(dom::Document* aDocument, nsPresContextType aType)
       mPendingInterruptFromTest(false),
       mInterruptsEnabled(false),
       mSendAfterPaintToContent(false),
-      mUseFocusColors(false),
       mDrawImageBackground(true),  // always draw the background
       mDrawColorBackground(true),
       // mNeverAnimate is initialised below, in constructor body

layout/base/nsPresContext.h

@@ -1220,9 +1220,6 @@ class nsPresContext : public nsISupports,
   unsigned mPendingInterruptFromTest : 1;
   unsigned mInterruptsEnabled : 1;
   unsigned mSendAfterPaintToContent : 1;
-  unsigned mUseFocusColors : 1;
-  unsigned mFocusRingOnAnything : 1;
-  unsigned mFocusRingStyle : 1;
   unsigned mDrawImageBackground : 1;
   unsigned mDrawColorBackground : 1;
   unsigned mNeverAnimate : 1;

layout/style/PreferenceSheet.h

@@ -37,7 +37,7 @@ struct PreferenceSheet {
     bool mUnderlineLinks = true;
     bool mUseFocusColors = false;
     uint8_t mFocusRingWidth = 1;
-    bool mFocusRingStyle = false;
+    uint8_t mFocusRingStyle = 1;
     bool mFocusRingOnAnything = false;
 
     void Load(bool aIsChrome);

modules/libpref/init/StaticPrefList.h

@@ -575,10 +575,11 @@ VARCACHE_PREF(
   uint32_t, 1
 )
 
+// 0=solid, 1=dotted
 VARCACHE_PREF(
   "browser.display.focus_ring_style",
    browser_display_focus_ring_style,
-  bool, false
+  uint32_t, 1
 )
 
 VARCACHE_PREF(