Update app_units to 0.3.1

The height test is removed in mime_sniffing_font_context because of rounding
changes in app_units. The rest of that test is still useful though, given it
will timeout if the font fails to be sniffed.

tests/wpt/metadata-css/css-backgrounds-3_dev/html4/background-repeat-repeat-x.htm.ini

@@ -1,4 +1,3 @@
 [background-repeat-repeat-x.htm]
   type: reftest
-  expected:
-    if os == "mac": FAIL
+  expected: FAIL

tests/wpt/metadata-css/css-backgrounds-3_dev/html4/background-repeat-repeat-y.htm.ini

@@ -1,4 +1,3 @@
 [background-repeat-repeat-y.htm]
   type: reftest
-  expected:
-    if os == "mac": FAIL
+  expected: FAIL

tests/wpt/metadata-css/css-flexbox-1_dev/html/flexbox_direction-row-reverse.htm.ini

@@ -1,4 +0,0 @@
-[flexbox_direction-row-reverse.htm]
-  type: reftest
-  expected:
-    if os == "mac": FAIL

tests/wpt/metadata-css/css-transforms-1_dev/html/transform-input-017.htm.ini

@@ -1,3 +1,4 @@
 [transform-input-017.htm]
   type: reftest
-  expected: FAIL
+  expected:
+    if os == "linux": FAIL

tests/wpt/metadata-css/css-transforms-1_dev/html/transform-input-018.htm.ini

@@ -1,3 +1,4 @@
 [transform-input-018.htm]
   type: reftest
-  expected: FAIL
+  expected:
+    if os == "linux": FAIL

tests/wpt/metadata-css/css21_dev/html4/background-repeat-repeat-x.htm.ini

@@ -1,4 +1,3 @@
 [background-repeat-repeat-x.htm]
   type: reftest
-  expected:
-    if os == "mac": FAIL
+  expected: FAIL

tests/wpt/metadata-css/css21_dev/html4/background-repeat-repeat-y.htm.ini

@@ -1,4 +1,3 @@
 [background-repeat-repeat-y.htm]
   type: reftest
-  expected:
-    if os == "mac": FAIL
+  expected: FAIL

tests/wpt/metadata-css/css21_dev/html4/c5525-fltwidth-003.htm.ini

@@ -0,0 +1,4 @@
+[c5525-fltwidth-003.htm]
+  type: reftest
+  expected:
+    if os == "linux": FAIL

tests/wpt/metadata-css/css21_dev/html4/floats-028.htm.ini

@@ -1,3 +1,4 @@
 [floats-028.htm]
   type: reftest
-  expected: FAIL
+  expected:
+    if os == "mac": FAIL

tests/wpt/mozilla/meta/MANIFEST.json

@@ -25673,7 +25673,7 @@
    "testharness"
   ],
   "mozilla/mime_sniffing_font_context.html": [
-   "cd2c1b14ce7b1810f4b75148e0fa9abbfceb780d",
+   "1311e72e0a0dafa6fae594ca1ce2deca164acd36",
    "testharness"
   ],
   "mozilla/mozbrowser/crossorigin_xhr.html": [

tests/wpt/mozilla/tests/mozilla/mime_sniffing_font_context.html

@@ -77,7 +77,6 @@ function checkFontLoaded() {
         return;
     }
     assert_not_equals(first.getBoundingClientRect().width, second.getBoundingClientRect().width);
-    assert_not_equals(first.getBoundingClientRect().height, second.getBoundingClientRect().height);
     this.done();
 }