Fix accessibility coordinates within iframes.

WebKit returns local coordinates within an iframe, we need
to convert them to page-global coordinates. In addition,
the test code needs to print page-global coordinates
(not screen-global) for easier debugging and reliable
test output.

BUG=171705
TBR=dtseng


Review URL: https://chromiumcodereview.appspot.com/12084028

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@179468 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/accessibility/browser_accessibility.cc

@@ -133,15 +133,30 @@ BrowserAccessibility* BrowserAccessibility::GetNextSibling() {
 gfx::Rect BrowserAccessibility::GetLocalBoundsRect() {
   gfx::Rect bounds = location_;
 
-  // Adjust top left position by the root document's scroll offset.
-  BrowserAccessibility* root = manager_->GetRoot();
-  int scroll_x = 0;
-  int scroll_y = 0;
-  if (!root->GetIntAttribute(AccessibilityNodeData::ATTR_SCROLL_X, &scroll_x) ||
-      !root->GetIntAttribute(AccessibilityNodeData::ATTR_SCROLL_Y, &scroll_y)) {
-    return bounds;
+  // Walk up the parent chain. Every time we encounter a Web Area, offset
+  // based on the scroll bars and then offset based on the origin of that
+  // nested web area.
+  BrowserAccessibility* parent = parent_;
+  bool need_to_offset_web_area =
+      (role_ == AccessibilityNodeData::ROLE_WEB_AREA);
+  while (parent) {
+    if (need_to_offset_web_area &&
+        parent->location().width() > 0 &&
+        parent->location().height() > 0) {
+      bounds.Offset(parent->location().x(), parent->location().y());
+      need_to_offset_web_area = false;
+    }
+    if (parent->role() == AccessibilityNodeData::ROLE_WEB_AREA) {
+      int sx = 0;
+      int sy = 0;
+      if (parent->GetIntAttribute(AccessibilityNodeData::ATTR_SCROLL_X, &sx) &&
+          parent->GetIntAttribute(AccessibilityNodeData::ATTR_SCROLL_Y, &sy)) {
+        bounds.Offset(-sx, -sy);
+      }
+      need_to_offset_web_area = true;
+    }
+    parent = parent->parent();
   }
-  bounds.Offset(-scroll_x, -scroll_y);
 
   return bounds;
 }

content/browser/accessibility/dump_accessibility_tree_browsertest.cc

@@ -363,6 +363,11 @@ IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest, AccessibilityHR) {
   RunTest(FILE_PATH_LITERAL("hr.html"));
 }
 
+IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest,
+                       AccessibilityIframeCoordinates) {
+  RunTest(FILE_PATH_LITERAL("iframe-coordinates.html"));
+}
+
 IN_PROC_BROWSER_TEST_F(DumpAccessibilityTreeTest, AccessibilityInputButton) {
   RunTest(FILE_PATH_LITERAL("input-button.html"));
 }

content/browser/accessibility/dump_accessibility_tree_helper_mac.mm

@@ -10,9 +10,12 @@
 #include "base/utf_string_conversions.h"
 #include "content/browser/accessibility/browser_accessibility_cocoa.h"
 #include "content/browser/accessibility/browser_accessibility_mac.h"
+#include "content/browser/accessibility/browser_accessibility_manager.h"
 
 namespace content {
+
 namespace {
+
 string16 Format(BrowserAccessibility* node,
                 const char *prefix,
                 SEL selector,
@@ -26,8 +29,43 @@ string16 Format(BrowserAccessibility* node,
   NSString* tmp = [NSString stringWithFormat:format_str, value];
   return UTF8ToUTF16([tmp cStringUsingEncoding:NSUTF8StringEncoding]);
 }
+
+string16 FormatPosition(BrowserAccessibility* node) {
+  // The NSAccessibility position of an object is in global coordinates and
+  // based on the lower-left corner of the object. To make this easier and less
+  // confusing, convert it to local window coordinates using the top-left
+  // corner when dumping the position.
+  BrowserAccessibility* root = node->manager()->GetRoot();
+  BrowserAccessibilityCocoa* cocoa_root = root->ToBrowserAccessibilityCocoa();
+  NSPoint root_position = [[cocoa_root position] pointValue];
+  NSSize root_size = [[cocoa_root size] sizeValue];
+  int root_top = -static_cast<int>(root_position.y + root_size.height);
+  int root_left = static_cast<int>(root_position.x);
+
+  BrowserAccessibilityCocoa* cocoa_node = node->ToBrowserAccessibilityCocoa();
+  NSPoint node_position = [[cocoa_node position] pointValue];
+  NSSize node_size = [[cocoa_node size] sizeValue];
+
+  NSString* position_str =
+      [NSString stringWithFormat:@"position=(%d, %d)",
+                static_cast<int>(node_position.x - root_left),
+                static_cast<int>(
+                    -node_position.y - node_size.height - root_top)];
+  return UTF8ToUTF16([position_str cStringUsingEncoding:NSUTF8StringEncoding]);
 }
 
+string16 FormatSize(BrowserAccessibility* node) {
+  BrowserAccessibilityCocoa* cocoa_node = node->ToBrowserAccessibilityCocoa();
+  NSSize node_size = [[cocoa_node size] sizeValue];
+  NSString* size_str =
+      [NSString stringWithFormat:@"size=(%d, %d)",
+                static_cast<int>(node_size.width),
+                static_cast<int>(node_size.height)];
+  return UTF8ToUTF16([size_str cStringUsingEncoding:NSUTF8StringEncoding]);
+}
+
+}  // namespace
+
 void DumpAccessibilityTreeHelper::Initialize() {}
 
 string16 DumpAccessibilityTreeHelper::ToString(BrowserAccessibility* node,
@@ -63,13 +101,14 @@ string16 DumpAccessibilityTreeHelper::ToString(BrowserAccessibility* node,
   Add(false, Format(node, "numberOfCharacters='",
                     @selector(numberOfCharacters), "'"));
   Add(false, Format(node, "orientation='", @selector(orientation), "'"));
-  Add(false, Format(node, "position='", @selector(position), "'"));
   Add(false, Format(node, "required='", @selector(required), "'"));
-  Add(false, Format(node, "size='", @selector(size), "'"));
   Add(false, Format(node, "url='", @selector(url), "'"));
   Add(false, Format(node, "visibleCharacterRange='",
                     @selector(visibleCharacterRange), "'"));
   Add(false, Format(node, "visited='", @selector(visited), "'"));
+  Add(false, FormatPosition(node));
+  Add(false, FormatSize(node));
+
   return ASCIIToUTF16(prefix) + FinishLine() + ASCIIToUTF16("\n");
 }
 

content/browser/accessibility/dump_accessibility_tree_helper_win.cc

@@ -12,6 +12,7 @@
 #include "base/string_util.h"
 #include "base/stringprintf.h"
 #include "base/utf_string_conversions.h"
+#include "content/browser/accessibility/browser_accessibility_manager.h"
 #include "content/browser/accessibility/browser_accessibility_win.h"
 #include "content/common/accessibility_node_data.h"
 #include "content/public/test/accessibility_test_utils_win.h"
@@ -100,10 +101,15 @@ string16 DumpAccessibilityTreeHelper::ToString(
   Add(false, L"description='" + description + L"'");
   Add(false, L"default_action='" + default_action + L"'");
   Add(false, L"keyboard_shortcut='" + keyboard_shortcut + L"'");
-  LONG x_left, y_top, width, height;
-  if (acc_obj->accLocation(&x_left, &y_top, &width, &height, variant_self) !=
-      S_FALSE) {
-    Add(false, StringPrintf(L"location=(%d, %d)", x_left, y_top));
+  BrowserAccessibility* root = node->manager()->GetRoot();
+  LONG left, top, width, height;
+  LONG root_left, root_top, root_width, root_height;
+  if (S_FALSE != acc_obj->accLocation(
+          &left, &top, &width, &height, variant_self) &&
+      S_FALSE != root->ToBrowserAccessibilityWin()->accLocation(
+          &root_left, &root_top, &root_width, &root_height, variant_self)) {
+    Add(false, StringPrintf(L"location=(%d, %d)",
+            left - root_left, top - root_top));
     Add(false, StringPrintf(L"size=(%d, %d)", width, height));
   }
   LONG index_in_parent;

content/test/data/accessibility/iframe-coordinates-expected-mac.txt

+AXWebArea position=(0, 0) size=(800, 600)
+    AXGroup position=(0, 0) size=(300, 150)
+        AXButton position=(25, 25) size=(250, 50)
+    AXGroup position=(0, 150) size=(300, 150)
+        AXButton position=(25, 175) size=(250, 50)
+    AXGroup position=(0, 300) size=(300, 150)
+        AXUnknown position=(0, 300) size=(300, 100)
+            AXUnknown position=(0, 0) size=(0, 0)
+                AXWebArea position=(0, 300) size=(300, 100)
+                    AXGroup position=(0, 300) size=(300, 100)
+                        AXButton position=(25, 325) size=(250, 50)
+    AXGroup position=(0, 450) size=(300, 150)
+        AXUnknown position=(0, 450) size=(150, 50)
+            AXUnknown position=(0, 0) size=(0, 0)
+                AXWebArea position=(0, 450) size=(300, 100)
+                    AXGroup position=(-150, 400) size=(300, 100)
+                        AXButton position=(-125, 425) size=(250, 50)
+                AXScrollBar position=(0, 0) size=(0, 0)
+                AXScrollBar position=(0, 0) size=(0, 0)

content/test/data/accessibility/iframe-coordinates-expected-win.txt

+ROLE_SYSTEM_DOCUMENT READONLY FOCUSABLE location=(0, 0) size=(800, 600)
+    IA2_ROLE_SECTION location=(0, 0) size=(300, 150)
+        ROLE_SYSTEM_PUSHBUTTON name='Button' FOCUSABLE location=(25, 25) size=(250, 50)
+    IA2_ROLE_SECTION location=(0, 150) size=(300, 150)
+        ROLE_SYSTEM_PUSHBUTTON name='Button' FOCUSABLE location=(25, 175) size=(250, 50)
+    IA2_ROLE_SECTION location=(0, 300) size=(300, 150)
+        ROLE_SYSTEM_CLIENT FOCUSABLE location=(0, 300) size=(300, 100)
+            IA2_ROLE_SCROLL_PANE location=(0, 0) size=(0, 0)
+                ROLE_SYSTEM_DOCUMENT READONLY FOCUSABLE location=(0, 300) size=(300, 100)
+                    IA2_ROLE_SECTION location=(0, 300) size=(300, 100)
+                        ROLE_SYSTEM_PUSHBUTTON name='Button' FOCUSABLE location=(25, 325) size=(250, 50)
+    IA2_ROLE_SECTION location=(0, 450) size=(300, 150)
+        ROLE_SYSTEM_CLIENT FOCUSABLE location=(0, 450) size=(150, 50)
+            IA2_ROLE_SCROLL_PANE location=(0, 0) size=(0, 0)
+                ROLE_SYSTEM_DOCUMENT READONLY FOCUSABLE location=(0, 450) size=(300, 100)
+                    IA2_ROLE_SECTION location=(-150, 400) size=(300, 100)
+                        ROLE_SYSTEM_PUSHBUTTON name='Button' FOCUSABLE location=(-125, 425) size=(250, 50)
+                ROLE_SYSTEM_SCROLLBAR location=(0, 0) size=(0, 0)
+                ROLE_SYSTEM_SCROLLBAR location=(0, 0) size=(0, 0)

content/test/data/accessibility/iframe-coordinates.html

+<!doctype html>
+<!--
+@MAC-DENY:title*
+@MAC-DENY:value*
+@MAC-ALLOW:position*
+@MAC-ALLOW:size*
+
+@WIN-DENY:title*
+@WIN-ALLOW:location*
+@WIN-ALLOW:size*
+-->
+<html>
+<head>
+<style>
+iframe {
+  border: 0;
+  margin: 0;
+  padding: 0;
+}
+div {
+  width: 300px;
+  height: 150px;
+}
+</style>
+</head>
+<body style="margin: 0; padding: 0;">
+
+<div>
+  <button style="margin: 25px; border: 0; width: 250px; height: 50px">
+    Button
+  </button>
+</div>
+
+<div>
+  <button style="margin: 25px; border: 0; width: 250px; height: 50px">
+    Button
+  </button>
+</div>
+
+<div><iframe id="frame1" style="width: 300px; height: 100px;"></iframe></div>
+
+<div><iframe id="frame2" style="width: 150px; height: 50px;"></iframe></div>
+
+<script>
+var frameCode =
+    '<body style="margin: 0; padding: 0;">\n' +
+    '<div style="width: 300px; height: 100px;">\n' +
+    '  <button style="margin: 25px; border: 0; width: 250px; height: 50px">\n' +
+    '    Button\n' +
+    '  </button>\n' +
+    '</div>\n' +
+    '</body>\n';
+
+function writeFrameCode(frame) {
+  var doc = frame.contentWindow.document;
+  doc.open();
+  doc.write(frameCode);
+  doc.close();
+}
+
+var frame1 = document.getElementById('frame1');
+writeFrameCode(frame1);
+
+var frame2 = document.getElementById('frame2');
+writeFrameCode(frame2);
+frame2.contentWindow.scrollTo(150, 50);
+</script>
+  
+</body>
+</html>