LibWeb: Bring CSS line-height closer to other engines

This patch makes a few changes to the way we calculate line-height:

- `line-height: normal` is now resolved using metrics from the used
  font (specifically, round(A + D + lineGap)).

- `line-height: calc(...)` is now resolved at style compute time.

- `line-height` values are now absolutized at style compute time.

As a consequence of the above, we no longer need to walk the DOM
ancestor chain looking for line-heights during style computation.
Instead, values are inherited, resolved and absolutized locally.

This is not only much faster, but also makes our line-height metrics
match those of other engines like Gecko and Blink.

Tests/LibWeb/Text/expected/FileAPI/Blob-empty-constructor.txt

@@ -1 +1 @@
-PASS
+PASS

Tests/LibWeb/Text/expected/FileAPI/Blob-intialized-with-strings-read-from-arrayBuffer.txt

@@ -1 +1 @@
-PASS
+PASS

Tests/LibWeb/Text/expected/FileAPI/Blob-intialized-with-strings-read-from-text.txt

@@ -1 +1 @@
-PASS
+PASS

Tests/LibWeb/Text/expected/HTML/HTMLInputElement-valueAsNumber.txt

@@ -43,4 +43,4 @@ file threw exception: InvalidStateError: valueAsNumber: Invalid input type used
 submit threw exception: InvalidStateError: valueAsNumber: Invalid input type used
 image threw exception: InvalidStateError: valueAsNumber: Invalid input type used
 reset threw exception: InvalidStateError: valueAsNumber: Invalid input type used
-button threw exception: InvalidStateError: valueAsNumber: Invalid input type used
+button threw exception: InvalidStateError: valueAsNumber: Invalid input type used

Tests/LibWeb/Text/expected/HTML/StructuredClone-object-primitives.txt

@@ -14,4 +14,4 @@ true
 1
 true
 [object ArrayBuffer]
-ERROR: DataCloneError: Cannot serialize Symbol
+ERROR: DataCloneError: Cannot serialize Symbol

Tests/LibWeb/Text/expected/HTML/StructuredClone-primitives.txt

@@ -5,4 +5,4 @@ false
 123
 123.456
 9007199254740991
-This is a string
+This is a string

Tests/LibWeb/Text/expected/HTML/Window-named-properties-elements.txt

@@ -3,4 +3,4 @@ true
 true
 true
 true
-true
+true

Tests/LibWeb/Text/expected/HTML/Window-named-properties-iframe.txt

@@ -1,2 +1,2 @@
    true
-true
+true

Tests/LibWeb/Text/expected/HTML/Window-prototype.txt

@@ -3,4 +3,4 @@
 [object WindowProperties]
 [object EventTarget]
 [object Object]
-null
+null

Tests/LibWeb/Text/expected/SVG/svg-href.txt

@@ -111,4 +111,4 @@ element.href.baseVal === element.href.animVal -> true
 element.getAttribute("xlink:href") -> null
 element.getAttribute("href") -> testSet
 animVal should be readonly:
-TypeError: Cannot set property 'animVal' of [object SVGAnimatedString]
+TypeError: Cannot set property 'animVal' of [object SVGAnimatedString]

Tests/LibWeb/Text/expected/Wasm/WebAssembly-instantiate.txt

@@ -13,4 +13,4 @@ FIXME: Run test for Float64Array. Not running due to flakiness.
 FIXME: Run test for BigUint64Array. Not running due to flakiness.
 FIXME: Run test for BigInt64Array. Not running due to flakiness.
 FIXME: Run test for DataView. Not running due to flakiness.
-FIXME: Run test for WebAssembly.Module. Not running due to flakiness.
+FIXME: Run test for WebAssembly.Module. Not running due to flakiness.

Tests/LibWeb/Text/expected/XHR/XMLHttpRequest-response-gives-Document.txt

@@ -1 +1 @@
-PASS
+PASS

Tests/LibWeb/Text/expected/XHR/XMLHttpRequest-response-is-blob.txt

@@ -1 +1 @@
-PASS
+PASS

Tests/LibWeb/Text/expected/XML/parser-namespace.txt

@@ -1,2 +1 @@
 PASS
-

Tests/LibWeb/Text/expected/anchor-element-with-javascript-url-href.txt

@@ -1 +1 @@
-  link clicked!
+  link clicked!

Tests/LibWeb/Text/expected/get-bounding-client-rect-display-none.txt

@@ -1 +1 @@
-   {"x":0,"y":0,"width":0,"height":0,"top":0,"right":0,"bottom":0,"left":0}
+   {"x":0,"y":0,"width":0,"height":0,"top":0,"right":0,"bottom":0,"left":0}

Tests/LibWeb/Text/expected/get-bounding-client-rect.txt

@@ -1,2 +1,2 @@
  inline   {"x":8,"y":500,"width":784,"height":150,"top":500,"right":792,"bottom":650,"left":8}
-{"x":8,"y":650,"width":41.296875,"height":17.46875,"top":650,"right":49.296875,"bottom":667.46875,"left":8}
+{"x":8,"y":650,"width":41.296875,"height":17,"top":650,"right":49.296875,"bottom":667,"left":8}

Tests/LibWeb/Text/expected/navigation/history-pushstate.txt

@@ -1 +1 @@
-  history object length has changed by 1
+  history object length has changed by 1

Tests/LibWeb/Text/expected/navigation/iframe-navigate-javascript-url.txt

@@ -1 +1 @@
- Hello from iframe navigated using javascript url
+ Hello from iframe navigated using javascript url

Tests/LibWeb/Text/expected/scroll-into-view-end.txt

@@ -1 +1 @@
-    The page has been scrolled to y: 600
+    The page has been scrolled to y: 600

Tests/LibWeb/Text/expected/scroll-into-view-start.txt

@@ -1 +1 @@
-    The page has been scrolled to y: 1000
+    The page has been scrolled to y: 1000

Tests/LibWeb/Text/expected/scroll-to-fragment.txt

@@ -1 +1 @@
-Take test     The page has been scrolled to y: 562.59375
+Take test     The page has been scrolled to y: 563