Expose IAccessible2 role IA2_ROLE_TOGGLE_BUTTON when aria-pressed used with any kind of button

R=dmazzoni@chromium.org
BUG=98979
TEST=Manually with accProbe


Review URL: http://codereview.chromium.org/9375045

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@121545 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 50 insertions, 0 deletions

diff --git a/AUTHORS b/AUTHORS
index dcba188..5f5480c 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -162,3 +162,4 @@ Eriq Augustine <eriq.augustine@gmail.com>
 Francois Kritzinger <francoisk777@gmail.com>
 Erik Hill <erikghill@gmail.com>
 Mao Yujie <maojie0924@gmail.com>
+Aaron Leventhal <aaronlevbugs@gmail.com>
diff --git a/content/browser/accessibility/browser_accessibility.cc b/content/browser/accessibility/browser_accessibility.cc
index f71f428..7972e3b 100644
--- a/content/browser/accessibility/browser_accessibility.cc
+++ b/content/browser/accessibility/browser_accessibility.cc
@@ -260,6 +260,31 @@ bool BrowserAccessibility::GetHtmlAttribute(
   return false;
 }
 
+bool BrowserAccessibility::GetAriaTristate(
+    const char* html_attr,
+    bool* is_defined,
+    bool* is_mixed) const {
+  *is_defined = false;
+  *is_mixed = false;
+
+  string16 value;
+  if (!GetHtmlAttribute(html_attr, &value) ||
+      value.empty() ||
+      EqualsASCII(value, "undefined")) {
+    return false;  // Not set (and *is_defined is also false)
+  }
+
+  *is_defined = true;
+
+  if (EqualsASCII(value, "true"))
+    return true;
+
+  if (EqualsASCII(value, "mixed"))
+    *is_mixed = true;
+
+  return false;  // Not set
+}
+
 bool BrowserAccessibility::HasState(WebAccessibility::State state_enum) const {
   return (state_ >> state_enum) & 1;
 }
diff --git a/content/browser/accessibility/browser_accessibility.h b/content/browser/accessibility/browser_accessibility.h
index d0317f3..452deb9 100644
--- a/content/browser/accessibility/browser_accessibility.h
+++ b/content/browser/accessibility/browser_accessibility.h
@@ -221,6 +221,22 @@ class CONTENT_EXPORT BrowserAccessibility {
   // returns true if found.
   bool GetHtmlAttribute(const char* attr, string16* value) const;
 
+  // Utility method to handle special cases for ARIA booleans, tristates and
+  // booleans which have a "mixed" state.
+  //
+  // Warning: the term "Tristate" is used loosely by the spec and here,
+  // as some attributes support a 4th state.
+  //
+  // The following attributes are appropriate to use with this method:
+  // aria-selected  (selectable)
+  // aria-grabbed   (grabbable)
+  // aria-expanded  (expandable)
+  // aria-pressed   (toggleable/pressable) -- supports 4th "mixed" state
+  // aria-checked   (checkable) -- supports 4th "mixed state"
+  bool GetAriaTristate(const char* attr_name,
+                       bool* is_defined,
+                       bool* is_mixed) const;
+
   // Returns true if the bit corresponding to the given state enum is 1.
   bool HasState(WebAccessibility::State state_enum) const;
 
diff --git a/content/browser/accessibility/browser_accessibility_win.cc b/content/browser/accessibility/browser_accessibility_win.cc
index 97f7814..98a264a 100644
--- a/content/browser/accessibility/browser_accessibility_win.cc
+++ b/content/browser/accessibility/browser_accessibility_win.cc
@@ -2990,6 +2990,14 @@ void BrowserAccessibilityWin::InitRoleAndState() {
       break;
     case WebAccessibility::ROLE_BUTTON:
       ia_role_ = ROLE_SYSTEM_PUSHBUTTON;
+      bool is_aria_pressed_defined;
+      bool is_mixed;
+      if (GetAriaTristate("aria-pressed", &is_aria_pressed_defined, &is_mixed))
+        ia_state_ |= STATE_SYSTEM_PRESSED;
+      if (is_aria_pressed_defined)
+        ia2_role_ = IA2_ROLE_TOGGLE_BUTTON;
+      if (is_mixed)
+        ia_state_ |= STATE_SYSTEM_MIXED;
       break;
     case WebAccessibility::ROLE_CELL:
       ia_role_ = ROLE_SYSTEM_CELL;