Bug 1097499 part 1 - Control support of 'text-combine-upright: digits' via a separate pref. r=heycam

MozReview-Commit-ID: JerTsxaQCL4

--HG--
extra : source : 999d1d2997591935fa1259fa42a91658da8ee078

layout/base/nsLayoutUtils.cpp

@@ -167,6 +167,7 @@ typedef nsStyleTransformMatrix::TransformReferenceBox TransformReferenceBox;
 /* static */ bool nsLayoutUtils::sCSSVariablesEnabled;
 /* static */ bool nsLayoutUtils::sInterruptibleReflowEnabled;
 /* static */ bool nsLayoutUtils::sSVGTransformBoxEnabled;
+/* static */ bool nsLayoutUtils::sTextCombineUprightDigitsEnabled;
 
 static ViewID sScrollIdCounter = FrameMetrics::START_SCROLL_ID;
 
@@ -7716,6 +7717,8 @@ nsLayoutUtils::Initialize()
                                "layout.interruptible-reflow.enabled");
   Preferences::AddBoolVarCache(&sSVGTransformBoxEnabled,
                                "svg.transform-box.enabled");
+  Preferences::AddBoolVarCache(&sTextCombineUprightDigitsEnabled,
+                               "layout.css.text-combine-upright-digits.enabled");
 
   for (auto& callback : kPrefCallbacks) {
     Preferences::RegisterCallbackAndCall(callback.func, callback.name);

layout/base/nsLayoutUtils.h

@@ -2411,6 +2411,10 @@ public:
     return sSVGTransformBoxEnabled;
   }
 
+  static bool TextCombineUprightDigitsEnabled() {
+    return sTextCombineUprightDigitsEnabled;
+  }
+
   /**
    * See comment above "font.size.inflation.mappingIntercept" in
    * modules/libpref/src/init/all.js .
@@ -2824,6 +2828,7 @@ private:
   static bool sCSSVariablesEnabled;
   static bool sInterruptibleReflowEnabled;
   static bool sSVGTransformBoxEnabled;
+  static bool sTextCombineUprightDigitsEnabled;
 
   /**
    * Helper function for LogTestDataForPaint().

layout/style/nsCSSParser.cpp

@@ -15165,6 +15165,9 @@ CSSParserImpl::ParseTextCombineUpright(nsCSSValue& aValue)
   // if 'digits', need to check for an explicit number [2, 3, 4]
   if (eCSSUnit_Enumerated == aValue.GetUnit() &&
       aValue.GetIntValue() == NS_STYLE_TEXT_COMBINE_UPRIGHT_DIGITS_2) {
+    if (!nsLayoutUtils::TextCombineUprightDigitsEnabled()) {
+      return false;
+    }
     if (!GetToken(true)) {
       return true;
     }

layout/style/test/property_database.js

@@ -5426,11 +5426,15 @@ if (IsCSSPropertyPrefEnabled("layout.css.text-combine-upright.enabled")) {
     inherited: true,
     type: CSS_TYPE_LONGHAND,
     initial_values: [ "none" ],
-    other_values: [ "all", "digits", "digits 2", "digits 3", "digits 4", "digits     3" ],
+    other_values: [ "all" ],
     invalid_values: [ "auto", "all 2", "none all", "digits -3", "digits 0",
                       "digits 12", "none 3", "digits 3.1415", "digits3", "digits 1",
                       "digits 3 all", "digits foo", "digits all", "digits 3.0" ]
   };
+  if (IsCSSPropertyPrefEnabled("layout.css.text-combine-upright-digits.enabled")) {
+    gCSSProperties["text-combine-upright"].other_values.push(
+      "digits", "digits 2", "digits 3", "digits 4", "digits     3");
+  }
 }
 
 if (IsCSSPropertyPrefEnabled("layout.css.masking.enabled")) {

modules/libpref/init/all.js

@@ -2432,6 +2432,8 @@ pref("layout.css.vertical-text.enabled", true);
 
 // Is support for CSS text-combine-upright (tate-chu-yoko) enabled?
 pref("layout.css.text-combine-upright.enabled", false);
+// Is support for CSS text-combine-upright: digits 2-4 enabled?
+pref("layout.css.text-combine-upright-digits.enabled", false);
 
 // Is support for object-fit and object-position enabled?
 pref("layout.css.object-fit-and-position.enabled", true);