Bug 1664109 - Fix `!=` operator of `EditorDOMRangeBase` r=m_kato

This is causes taking back bugs in
`WSRunScanner::GetNewInvisibleLeadingWhiteSpaceRangeIfSplittingAt()` and
`WSRunScanner::GetNewInvisibleTrailingWhiteSpaceRangeIfSplittingAt()`  (I.e.,
they were fixed by bug 1647556).  Therefore, this removes the odd `if` blocks
which are pointed with `XXX` comment for avoiding "regressions" (without them,
some WPTs for `InputEvents.getTargetRanges()` become failure).

Depends on D89582

Differential Revision: https://phabricator.services.mozilla.com/D89869

editor/libeditor/EditorDOMPoint.h

@@ -1100,7 +1100,7 @@ class EditorDOMRangeBase final {
   }
   template <typename OtherRangeType>
   bool operator!=(const OtherRangeType& aOther) const {
-    return *this == aOther;
+    return !(*this == aOther);
   }
 
   EditorDOMRangeInTexts GetAsInTexts() const {

editor/libeditor/WSRunObject.h

@@ -959,12 +959,6 @@ class MOZ_STACK_CLASS WSRunScanner final {
       if (!trailingWhiteSpaceRange.IsPositioned()) {
         return trailingWhiteSpaceRange;
       }
-      // XXX Why don't we need to treat new trailing white-spaces are invisible
-      //     when the trailing white-spaces are only the content in current
-      //     line?
-      if (trailingWhiteSpaceRange != InvisibleLeadingWhiteSpaceRangeRef()) {
-        return EditorDOMRange();
-      }
       // If the point is before the trailing white-spaces, the new line won't
       // start with leading white-spaces.
       if (aPointToSplit.IsBefore(trailingWhiteSpaceRange.StartRef())) {
@@ -1008,12 +1002,6 @@ class MOZ_STACK_CLASS WSRunScanner final {
       if (!leadingWhiteSpaceRange.IsPositioned()) {
         return leadingWhiteSpaceRange;
       }
-      // XXX Why don't we need to treat new leading white-spaces are invisible
-      //     when the leading white-spaces are only the content in current
-      //     line?
-      if (leadingWhiteSpaceRange != InvisibleTrailingWhiteSpaceRangeRef()) {
-        return EditorDOMRange();
-      }
       // If the point equals or is after the leading white-spaces, the line
       // will end without trailing white-spaces.
       if (leadingWhiteSpaceRange.EndRef().IsBefore(aPointToSplit)) {

editor/libeditor/crashtests/crashtests.list

@@ -96,7 +96,7 @@ load 1402526.html
 pref(dom.document.exec_command.nested_calls_allowed,true) asserts(1) load 1402904.html # assertion is that mutation event listener caused by execCommand calls another execCommand
 pref(dom.document.exec_command.nested_calls_allowed,true) asserts(1) load 1405747.html # assertion is that mutation event listener caused by execCommand calls another execCommand
 load 1405897.html
-asserts(6) load 1408170.html # 4: assertion in WSRunScanner::GetEditableBlockParentOrTopmotEditableInlineContent(), 2: assertion in WhiteSpaceVisibilityKeeper::DeleteInvisibleASCIIWhiteSpacesInternal()
+asserts(4) load 1408170.html # 4: assertion in WSRunScanner::GetEditableBlockParentOrTopmotEditableInlineContent()
 asserts(0-1) load 1414581.html
 load 1415231.html
 load 1423767.html

editor/libeditor/tests/test_bug1425997.html

@@ -24,9 +24,9 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=1425997
 
 <script class="testbody" type="application/javascript">
 SimpleTest.waitForExplicitFinish();
-// 3 assertions are recorded due to nested execCommand() but not a problem.
+// 2 assertions are recorded due to nested execCommand() but not a problem.
 // They are necessary to detect invalid method call without mutation event listers.
-SimpleTest.expectAssertions(3, 3);
+SimpleTest.expectAssertions(2, 2);
 SimpleTest.waitForFocus(async function() {
   await SpecialPowers.pushPrefEnv({set: [["dom.document.exec_command.nested_calls_allowed", true]]});
   let selection = window.getSelection();

editor/libeditor/tests/test_bug772796.html

@@ -144,8 +144,6 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=772796
     /** Test for Bug 772796 **/
 
     SimpleTest.waitForExplicitFinish();
-    SimpleTest.expectAssertions(13); // assertion in WhiteSpaceVisibilityKeeper::DeleteInvisibleASCIIWhiteSpaces()
-
     SimpleTest.waitForFocus(function() {
       var sel = window.getSelection();
       var theEdit = document.getElementById("editable");

testing/web-platform/meta/input-events/input-events-get-target-ranges-backspace.tentative.html.ini

@@ -20,9 +20,6 @@
   [Backspace at "<p>abc   </p><pre>[\]   def</pre>"]
     expected: FAIL
 
-  [Backspace at "<div>abc   <p>   [\]def<br>ghi</p></div>"]
-    expected: FAIL
-
   [Backspace at "<p> a[\]bc</p>"]
     expected: FAIL
 
@@ -38,9 +35,6 @@
   [Backspace at "<p>abc   [</p><p>\]   def</p>"]
     expected: FAIL
 
-  [Backspace at "<div><p>abc   </p>   [\]def</div>"]
-    expected: FAIL
-
   [Backspace at "<p>a<span>b</span>[\]c</p>"]
     expected: FAIL