Bug 1726297 - part 2: Make `ContentEventHandler::Get(First|Last)Frame…

…InRangeForTextRect` ignore invisible nodes r=smaug

The callers of them want to return text rect for first visible thing in the
given range to make IME place UI around there.  Therefore, it should ignore
invisible text which won't be interactive with IME.

Differential Revision: https://phabricator.services.mozilla.com/D160591

dom/events/ContentEventHandler.cpp

@@ -1505,27 +1505,36 @@ ContentEventHandler::GetFirstFrameInRangeForTextRect(
       break;
     }
 
-    if (!node->IsContent()) {
+    auto* content = nsIContent::FromNode(node);
+    if (MOZ_UNLIKELY(!content)) {
       continue;
     }
 
-    if (node->IsText()) {
+    // If the node is invisible (e.g., the node is or is in an invisible node or
+    // it's a white-space only text node around a block boundary), we should
+    // ignore it.
+    if (!content->GetPrimaryFrame()) {
+      continue;
+    }
+
+    if (auto* textNode = Text::FromNode(content)) {
       // If the range starts at the end of a text node, we need to find
       // next node which causes text.
-      const uint32_t offsetInNode =
-          node == aRawRange.GetStartContainer() ? aRawRange.StartOffset() : 0u;
-      if (offsetInNode < node->Length()) {
-        nodePosition = {node, offsetInNode};
+      const uint32_t offsetInNode = textNode == aRawRange.GetStartContainer()
+                                        ? aRawRange.StartOffset()
+                                        : 0u;
+      if (offsetInNode < textNode->TextDataLength()) {
+        nodePosition = {textNode, offsetInNode};
         break;
       }
       continue;
     }
 
     // If the element node causes a line break before it, it's the first
     // node causing text.
-    if (ShouldBreakLineBefore(*node->AsContent(), mRootElement) ||
-        IsPaddingBR(*node->AsContent())) {
-      nodePosition = {node, 0u};
+    if (ShouldBreakLineBefore(*content, mRootElement) ||
+        IsPaddingBR(*content)) {
+      nodePosition = {content, 0u};
     }
   }
 
@@ -1592,14 +1601,26 @@ ContentEventHandler::GetLastFrameInRangeForTextRect(const RawRange& aRawRange) {
       break;
     }
 
-    if (!node->IsContent() || node == nextNodeOfRangeEnd) {
+    if (node == nextNodeOfRangeEnd) {
+      continue;
+    }
+
+    auto* content = nsIContent::FromNode(node);
+    if (MOZ_UNLIKELY(!content)) {
+      continue;
+    }
+
+    // If the node is invisible (e.g., the node is or is in an invisible node or
+    // it's a white-space only text node around a block boundary), we should
+    // ignore it.
+    if (!content->GetPrimaryFrame()) {
       continue;
     }
 
-    if (node->IsText()) {
-      nodePosition = {node, node == aRawRange.GetEndContainer()
-                                ? aRawRange.EndOffset()
-                                : node->Length()};
+    if (auto* textNode = Text::FromNode(node)) {
+      nodePosition = {textNode, textNode == aRawRange.GetEndContainer()
+                                    ? aRawRange.EndOffset()
+                                    : textNode->TextDataLength()};
 
       // If the text node is empty or the last node of the range but the index
       // is 0, we should store current position but continue looking for
@@ -1612,9 +1633,9 @@ ContentEventHandler::GetLastFrameInRangeForTextRect(const RawRange& aRawRange) {
       break;
     }
 
-    if (ShouldBreakLineBefore(*node->AsContent(), mRootElement) ||
-        IsPaddingBR(*node->AsContent())) {
-      nodePosition = {node, 0u};
+    if (ShouldBreakLineBefore(*content, mRootElement) ||
+        IsPaddingBR(*content)) {
+      nodePosition = {content, 0u};
       break;
     }
   }