Move IA2 attribute collection code to AXPlatformNodeBase

This will allow us to share this code with the Aura Linux implementation
in a future change. We also create a new abstract class to collect these
attributes while maintaining performance between the different
platforms. Currently there is only an implementation of this class for
Windows.

Bug: 866612
Change-Id: I5cb84b9f226e976ac2b199149ea897831a48d175
Reviewed-on: https://chromium-review.googlesource.com/1152977
Commit-Queue: Martin Robinson <mrobinson@igalia.com>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579353}

ui/accessibility/platform/ax_platform_node_auralinux.cc

@@ -1689,4 +1689,11 @@ AtkAttributeSet* AXPlatformNodeAuraLinux::AddIntAttributeToAtkAttributeSet(
   return attributes;
 }
 
+void AXPlatformNodeAuraLinux::AddAttributeToList(
+    const char* name,
+    const char* value,
+    PlatformAttributeList* attributes) {
+  NOTREACHED();
+}
+
 }  // namespace ui

ui/accessibility/platform/ax_platform_node_auralinux.h

@@ -90,6 +90,11 @@ class AXPlatformNodeAuraLinux : public AXPlatformNodeBase {
   void Init(AXPlatformNodeDelegate* delegate) override;
   int GetIndexInParent() override;
 
+ protected:
+  void AddAttributeToList(const char* name,
+                          const char* value,
+                          PlatformAttributeList* attributes) override;
+
  private:
   enum AtkInterfaces {
     ATK_ACTION_INTERFACE,

ui/accessibility/platform/ax_platform_node_base.h

@@ -5,6 +5,8 @@
 #ifndef UI_ACCESSIBILITY_PLATFORM_AX_PLATFORM_NODE_BASE_H_
 #define UI_ACCESSIBILITY_PLATFORM_AX_PLATFORM_NODE_BASE_H_
 
+#include <string>
+
 #include "base/macros.h"
 #include "ui/accessibility/ax_enums.mojom.h"
 #include "ui/accessibility/platform/ax_platform_node.h"
@@ -191,6 +193,46 @@ class AX_EXPORT AXPlatformNodeBase : public AXPlatformNode {
   // Sets the text selection in this object if possible.
   bool SetTextSelection(int start_offset, int end_offset);
 
+  // Compute the attributes exposed via platform accessibility objects and put
+  // them into an attribute list, |attributes|. Currently only used by
+  // IAccessible2 on Windows, but will soon be shared with other ports.
+  using PlatformAttributeList = std::vector<base::string16>;
+  void ComputeAttributes(PlatformAttributeList* attributes);
+
+  // If the string attribute |attribute| is present, add its value as an
+  // IAccessible2 attribute with the name |name|.
+  void AddAttributeToList(const ax::mojom::StringAttribute attribute,
+                          const char* name,
+                          PlatformAttributeList* attributes);
+
+  // If the bool attribute |attribute| is present, add its value as an
+  // IAccessible2 attribute with the name |name|.
+  void AddAttributeToList(const ax::mojom::BoolAttribute attribute,
+                          const char* name,
+                          PlatformAttributeList* attributes);
+
+  // If the int attribute |attribute| is present, add its value as an
+  // IAccessible2 attribute with the name |name|.
+  void AddAttributeToList(const ax::mojom::IntAttribute attribute,
+                          const char* name,
+                          PlatformAttributeList* attributes);
+
+  // A helper to add the given string value to |attributes|.
+  virtual void AddAttributeToList(const char* name,
+                                  const std::string& value,
+                                  PlatformAttributeList* attributes);
+
+  // A pure virtual method that subclasses use to actually add the attribute to
+  // |attributes|.
+  virtual void AddAttributeToList(const char* name,
+                                  const char* value,
+                                  PlatformAttributeList* attributes) = 0;
+
+  // Escapes characters in string attributes as required by the IA2 Spec
+  // and AT-SPI2. It's okay for input to be the same as output.
+  static void SanitizeStringAttribute(const std::string& input,
+                                      std::string* output);
+
  private:
   DISALLOW_COPY_AND_ASSIGN(AXPlatformNodeBase);
 };

ui/accessibility/platform/ax_platform_node_mac.h

@@ -29,6 +29,11 @@ class AXPlatformNodeMac : public AXPlatformNodeBase {
   void Destroy() override;
   int GetIndexInParent() override;
 
+ protected:
+  void AddAttributeToList(const char* name,
+                          const char* value,
+                          PlatformAttributeList* attributes) override;
+
  private:
   ~AXPlatformNodeMac() override;
 

ui/accessibility/platform/ax_platform_node_mac.mm

@@ -1006,4 +1006,10 @@ bool IsNameExposedInAXValueForRole(ax::mojom::Role role) {
   }
 }
 
+void AXPlatformNodeMac::AddAttributeToList(const char* name,
+                                           const char* value,
+                                           PlatformAttributeList* attributes) {
+  NOTREACHED();
+}
+
 }  // namespace ui

ui/accessibility/platform/ax_platform_node_win.h

@@ -925,6 +925,11 @@ class AX_EXPORT __declspec(uuid("26f5641a-246d-457b-a96d-07f3fae6acf2"))
   // Convert from a IA2TextBoundaryType to a TextBoundaryType.
   TextBoundaryType IA2TextBoundaryToTextBoundary(IA2TextBoundaryType type);
 
+  // A helper to add the given string value to |attributes|.
+  void AddAttributeToList(const char* name,
+                          const char* value,
+                          PlatformAttributeList* attributes) override;
+
  private:
   int MSAAEvent(ax::mojom::Event event);
   bool IsWebAreaForPresentationalIframe();
@@ -934,32 +939,9 @@ class AX_EXPORT __declspec(uuid("26f5641a-246d-457b-a96d-07f3fae6acf2"))
   HRESULT GetStringAttributeAsBstr(ax::mojom::StringAttribute attribute,
                                    BSTR* value_bstr) const;
 
-  // Escapes characters in string attributes as required by the IA2 Spec.
-  // It's okay for input to be the same as output.
-  static void SanitizeStringAttributeForIA2(const base::string16& input,
-                                            base::string16* output);
-
   // Sets the selection given a start and end offset in IA2 Hypertext.
   void SetIA2HypertextSelection(LONG start_offset, LONG end_offset);
 
-  // If the string attribute |attribute| is present, add its value as an
-  // IAccessible2 attribute with the name |ia2_attr|.
-  void StringAttributeToIA2(std::vector<base::string16>& attributes,
-                            ax::mojom::StringAttribute attribute,
-                            const char* ia2_attr);
-
-  // If the bool attribute |attribute| is present, add its value as an
-  // IAccessible2 attribute with the name |ia2_attr|.
-  void BoolAttributeToIA2(std::vector<base::string16>& attributes,
-                          ax::mojom::BoolAttribute attribute,
-                          const char* ia2_attr);
-
-  // If the int attribute |attribute| is present, add its value as an
-  // IAccessible2 attribute with the name |ia2_attr|.
-  void IntAttributeToIA2(std::vector<base::string16>& attributes,
-                         ax::mojom::IntAttribute attribute,
-                         const char* ia2_attr);
-
   // Escapes characters in string attributes as required by the UIA Aria
   // Property Spec. It's okay for input to be the same as output.
   static void SanitizeStringAttributeForUIAAriaProperty(