Spatial navigation enhancements

public/web/WebSettings.h

Index: public/web/WebSettings.h
diff --git a/public/web/WebSettings.h b/public/web/WebSettings.h
index 94df385ee14f0ea9c4e272c82cdb959d01e63240..78e923b2b1f96663d0ea6edc7265286ce6fddc5c 100644
--- a/public/web/WebSettings.h
+++ b/public/web/WebSettings.h
@@ -148,6 +148,13 @@ public:
     virtual void setShowPaintRects(bool) = 0;
     virtual void setShrinksStandaloneImagesToFit(bool) = 0;
     virtual void setSmartInsertDeleteEnabled(bool) = 0;
+    // Spatial navigation feature, when enabled, improves the experience
+    // of keyboard-controlling the web pages which originally were not designed
+    // for keyboard navigation. It allows to use arrow keys to move focus between
+    // the adjacent HTML elements. As a side effect, it extends the criteria for
+    // elements to be focusable to include any element which has click or keyboard
+    // event handlers specified. User can also trigger click handlers for such
+    // elements using SPACE or ENTER keys.
     virtual void setSpatialNavigationEnabled(bool) = 0;
     virtual void setStandardFontFamily(const WebString&, UScriptCode = USCRIPT_COMMON) = 0;
     virtual void setSupportDeprecatedTargetDensityDPI(bool) = 0;