Bug 1826868 - Remove useless Title IPC sync message. r=morgan,ipc-reviewers,mccr8

The message wasn't doing anything useful on Mac. Took the opportunity to
correcty expose the AXTitle/AXDescription of headings.

Differential Revision: https://phabricator.services.mozilla.com/D176824

accessible/ipc/RemoteAccessibleShared.h

@@ -176,7 +176,6 @@ virtual nsIntRect BoundsInCSSPixels() const override;
 
 virtual void Language(nsAString& aLocale) override;
 void DocType(nsString& aType);
-void Title(nsString& aTitle);
 void MimeType(nsString aMime);
 void URLDocTypeMimeType(nsString& aURL, nsString& aDocType,
                         nsString& aMimeType);

accessible/ipc/other/DocAccessibleChild.cpp

@@ -1331,17 +1331,6 @@ mozilla::ipc::IPCResult DocAccessibleChild::RecvDocType(const uint64_t& aID,
   return IPC_OK();
 }
 
-mozilla::ipc::IPCResult DocAccessibleChild::RecvTitle(const uint64_t& aID,
-                                                      nsString* aTitle) {
-  LocalAccessible* acc = IdToAccessible(aID);
-  if (acc) {
-    mozilla::ErrorResult rv;
-    acc->GetContent()->GetTextContent(*aTitle, rv);
-  }
-
-  return IPC_OK();
-}
-
 mozilla::ipc::IPCResult DocAccessibleChild::RecvMimeType(const uint64_t& aID,
                                                          nsString* aMime) {
   LocalAccessible* acc = IdToAccessible(aID);

accessible/ipc/other/DocAccessibleChild.h

@@ -395,8 +395,6 @@ class DocAccessibleChild : public DocAccessibleChildBase {
                                                nsString* aLocale) override;
   virtual mozilla::ipc::IPCResult RecvDocType(const uint64_t& aID,
                                               nsString* aType) override;
-  virtual mozilla::ipc::IPCResult RecvTitle(const uint64_t& aID,
-                                            nsString* aTitle) override;
   virtual mozilla::ipc::IPCResult RecvMimeType(const uint64_t& aID,
                                                nsString* aMime) override;
   virtual mozilla::ipc::IPCResult RecvURLDocTypeMimeType(

accessible/ipc/other/PDocAccessible.ipdl

@@ -318,7 +318,6 @@ child:
 
   [Nested=inside_sync] sync Language(uint64_t aID) returns(nsString aLocale);
   [Nested=inside_sync] sync DocType(uint64_t aID) returns(nsString aType);
-  [Nested=inside_sync] sync Title(uint64_t aID) returns(nsString aTitle);
   [Nested=inside_sync] sync MimeType(uint64_t aID) returns(nsString aMime);
   [Nested=inside_sync] sync URLDocTypeMimeType(uint64_t aID) returns(nsString aURL, nsString aDocType, nsString aMimeType);
 

accessible/ipc/other/RemoteAccessible.cpp

@@ -951,10 +951,6 @@ void RemoteAccessible::DocType(nsString& aType) {
   Unused << mDoc->SendDocType(mID, &aType);
 }
 
-void RemoteAccessible::Title(nsString& aTitle) {
-  Unused << mDoc->SendTitle(mID, &aTitle);
-}
-
 void RemoteAccessible::MimeType(nsString aMime) {
   Unused << mDoc->SendMimeType(mID, &aMime);
 }

accessible/mac/mozHTMLAccessible.mm

@@ -18,16 +18,13 @@ using namespace mozilla::a11y;
 
 - (NSString*)moxTitle {
   nsAutoString title;
-  if (LocalAccessible* acc = mGeckoAccessible->AsLocal()) {
-    mozilla::ErrorResult rv;
-    // XXX use the flattening API when there are available
-    // see bug 768298
-    acc->GetContent()->GetTextContent(title, rv);
-  } else if (RemoteAccessible* proxy = mGeckoAccessible->AsRemote()) {
-    proxy->Title(title);
-  }
 
-  title.CompressWhitespace();
+  ENameValueFlag flag = mGeckoAccessible->Name(title);
+  if (flag != eNameFromSubtree) {
+    // If this is a name via relation or attribute (eg. aria-label)
+    // it will be provided via AXDescription.
+    return nil;
+  }
 
   return nsCocoaUtils::ToNSString(title);
 }

accessible/tests/browser/mac/browser_heading.js

@@ -13,7 +13,7 @@ addAccessibleTask(
   <h1 id="single-line-content">We’re building a richer search experience</h1>
   <h1 id="multi-lines-content">
 We’re building a
-richer
+richest
 search experience
   </h1>
   `,
@@ -33,7 +33,45 @@ search experience
     );
     is(
       multiLinesContentHeading.getAttributeValue("AXTitle"),
-      "We’re building a richer search experience"
+      "We’re building a richest search experience"
     );
   }
 );
+
+/**
+ * Test AXTitle/AXDescription attributes of heading elements
+ */
+addAccessibleTask(
+  `
+  <h1 id="a">Hello <a href="#">world</a></h1>
+  <h1 id="b">Hello</h1>
+  <h1 id="c" aria-label="Goodbye">Hello</h1>
+  `,
+  async (browser, accDoc) => {
+    const a = getNativeInterface(accDoc, "a");
+    is(
+      a.getAttributeValue("AXTitle"),
+      "Hello world",
+      "Correct AXTitle for 'a'"
+    );
+    ok(
+      !a.getAttributeValue("AXDescription"),
+      "'a' Should not have AXDescription"
+    );
+
+    const b = getNativeInterface(accDoc, "b");
+    is(b.getAttributeValue("AXTitle"), "Hello", "Correct AXTitle for 'b'");
+    ok(
+      !b.getAttributeValue("AXDescription"),
+      "'b' Should not have AXDescription"
+    );
+
+    const c = getNativeInterface(accDoc, "c");
+    is(
+      c.getAttributeValue("AXDescription"),
+      "Goodbye",
+      "Correct AXDescription for 'c'"
+    );
+    ok(!c.getAttributeValue("AXTitle"), "'c' Should not have AXTitle");
+  }
+);

accessible/tests/browser/mac/browser_link.js

@@ -200,7 +200,7 @@ addAccessibleTask(
       link4
         .getAttributeValue("AXLinkedUIElements")[0]
         .getAttributeValue("AXTitle"),
-      "",
+      null,
       "Link 4 is linked to the heading"
     );
     is(

ipc/ipdl/sync-messages.ini

@@ -341,9 +341,6 @@ platform = notwin
 [PDocAccessible::DocType]
 description = Legacy a11y IPC
 platform = notwin
-[PDocAccessible::Title]
-description = Legacy a11y IPC
-platform = notwin
 [PDocAccessible::MimeType]
 description = Legacy a11y IPC
 platform = notwin