Auto merge of #17581 - mbrubeck:incremental, r=pcwalton

Fix incremental layout bugs for absolute and cleared elements

Fixes #17307.  <del>There were two underlying bugs:</del>

* <del>Nodes were not marked dirty when their style attribute changed.</del>

* BaseFlow flags set during flow construction could get out of sync with the element's style if repair_style was called.

---

- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #17307
- [x] There are tests for these changes

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components/style/servo/restyle_damage.rs

@@ -202,7 +202,7 @@ fn compute_damage(old: &ServoComputedValues, new: &ServoComputedValues) -> Servo
     add_if_not_equal!(old, new, damage,
                       [REPAINT, REPOSITION, STORE_OVERFLOW, BUBBLE_ISIZES, REFLOW_OUT_OF_FLOW,
                        REFLOW, RECONSTRUCT_FLOW], [
-        get_box.float, get_box.display, get_box.position, get_counters.content,
+        get_box.clear, get_box.float, get_box.display, get_box.position, get_counters.content,
         get_counters.counter_reset, get_counters.counter_increment,
         get_inheritedbox._servo_under_display_none,
         get_list.quotes, get_list.list_style_type,