Remove lots of code from the WebWidget/WebView/WebFrame layer.

sky/engine/public/web/WebWidget.h

Index: sky/engine/public/web/WebWidget.h
diff --git a/sky/engine/public/web/WebWidget.h b/sky/engine/public/web/WebWidget.h
index 50ba10af3965213e61ff1e6a2d5bf12e39433d82..5305109a2f71fadb45aaeee9ebcb8ecb7eb01dc1 100644
--- a/sky/engine/public/web/WebWidget.h
+++ b/sky/engine/public/web/WebWidget.h
@@ -54,49 +54,19 @@ template <typename T> class WebVector;
 class WebWidget {
 public:
     // This method closes and deletes the WebWidget.
-    virtual void close() { }
+    virtual void close() = 0;
 
     // Returns the current size of the WebWidget.
-    virtual WebSize size() { return WebSize(); }
-
-    // Used to group a series of resize events. For example, if the user
-    // drags a resizer then willStartLiveResize will be called, followed by a
-    // sequence of resize events, ending with willEndLiveResize when the user
-    // lets go of the resizer.
-    virtual void willStartLiveResize() { }
+    virtual WebSize size() = 0;
 
     // Called to resize the WebWidget.
-    virtual void resize(const WebSize&) { }
-
-    // Ends a group of resize events that was started with a call to
-    // willStartLiveResize.
-    virtual void willEndLiveResize() { }
-
-    // Called to notify the WebWidget of entering/exiting fullscreen mode. The
-    // resize method may be called between will{Enter,Exit}FullScreen and
-    // did{Enter,Exit}FullScreen.
-    virtual void willEnterFullScreen() { }
-    virtual void didEnterFullScreen() { }
-    virtual void willExitFullScreen() { }
-    virtual void didExitFullScreen() { }
-
-    // Called to update imperative animation state. This should be called before
-    // paint, although the client can rate-limit these calls.
-    // FIXME: Remove this function once Chrome side patch lands.
-    void animate(double monotonicFrameBeginTime)
-    {
-        beginFrame(WebBeginFrameArgs(monotonicFrameBeginTime));
-    }
-    virtual void beginFrame(const WebBeginFrameArgs& frameTime) { }
-
-    // Called to notify that a previously begun frame was finished and
-    // committed to the compositor. This is used to schedule lower priority
-    // work after tasks such as input processing and painting.
-    virtual void didCommitFrameToCompositor() { }
+    virtual void resize(const WebSize&) = 0;
+
+    virtual void beginFrame(const WebBeginFrameArgs& frameTime) = 0;
 
     // Called to layout the WebWidget. This MUST be called before Paint,
     // and it may result in calls to WebWidgetClient::didInvalidateRect.
-    virtual void layout() { }
+    virtual void layout() = 0;
 
     // Called to paint the rectangular region within the WebWidget
     // onto the specified canvas at (viewPort.x,viewPort.y). You MUST call
@@ -105,32 +75,23 @@ public:
     // changes are made to the WebWidget (e.g., once events are
     // processed, it should be assumed that another call to layout is
     // warranted before painting again).
-    virtual void paint(WebCanvas*, const WebRect& viewPort) { }
+    virtual void paint(WebCanvas*, const WebRect& viewPort) = 0;
 
     // Returns true if we've started tracking repaint rectangles.
-    virtual bool isTrackingRepaints() const { return false; }
-
-    // Indicates that the compositing surface associated with this WebWidget is
-    // ready to use.
-    virtual void setCompositorSurfaceReady() { }
-
-    // Called to inform the WebWidget of a change in theme.
-    // Implementors that cache rendered copies of widgets need to re-render
-    // on receiving this message
-    virtual void themeChanged() { }
+    virtual bool isTrackingRepaints() const = 0;
 
     // Called to inform the WebWidget of an input event. Returns true if
     // the event has been processed, false otherwise.
-    virtual bool handleInputEvent(const WebInputEvent&) { return false; }
+    virtual bool handleInputEvent(const WebInputEvent&) = 0;
 
     // Called to inform the WebWidget of the mouse cursor's visibility.
-    virtual void setCursorVisibilityState(bool isVisible) { }
+    virtual void setCursorVisibilityState(bool isVisible) = 0;
 
     // Called to inform the WebWidget that mouse capture was lost.
-    virtual void mouseCaptureLost() { }
+    virtual void mouseCaptureLost() = 0;
 
     // Called to inform the WebWidget that it has gained or lost keyboard focus.
-    virtual void setFocus(bool) { }
+    virtual void setFocus(bool) = 0;
 
     // Called to inform the WebWidget of a new composition text.
     // If selectionStart and selectionEnd has the same value, then it indicates
@@ -141,7 +102,7 @@ public:
         const WebString& text,
         const WebVector<WebCompositionUnderline>& underlines,
         int selectionStart,
-        int selectionEnd) { return false; }
+        int selectionEnd) = 0;
 
     enum ConfirmCompositionBehavior {
         DoNotKeepSelection,
@@ -151,8 +112,8 @@ public:
     // Called to inform the WebWidget to confirm an ongoing composition.
     // This method is same as confirmComposition(WebString());
     // Returns true if there is an ongoing composition.
-    virtual bool confirmComposition() { return false; } // Deprecated
-    virtual bool confirmComposition(ConfirmCompositionBehavior selectionBehavior) { return false; }
+    virtual bool confirmComposition() = 0; // Deprecated
+    virtual bool confirmComposition(ConfirmCompositionBehavior selectionBehavior) = 0;
 
     // Called to inform the WebWidget to confirm an ongoing composition with a
     // new composition text. If the text is empty then the current composition
@@ -160,57 +121,26 @@ public:
     // current selection and inserts the text. This method has no effect if
     // there is no ongoing composition and the text is empty.
     // Returns true if there is an ongoing composition or the text is inserted.
-    virtual bool confirmComposition(const WebString& text) { return false; }
+    virtual bool confirmComposition(const WebString& text) = 0;
 
     // Fetches the character range of the current composition, also called the
     // "marked range." Returns true and fills the out-paramters on success;
     // returns false on failure.
-    virtual bool compositionRange(size_t* location, size_t* length) { return false; }
+    virtual bool compositionRange(size_t* location, size_t* length) = 0;
 
     // Returns information about the current text input of this WebWidget.
-    virtual WebTextInputInfo textInputInfo() { return WebTextInputInfo(); }
-
-    // Returns the anchor and focus bounds of the current selection.
-    // If the selection range is empty, it returns the caret bounds.
-    virtual bool selectionBounds(WebRect& anchor, WebRect& focus) const { return false; }
+    virtual WebTextInputInfo textInputInfo() = 0;
 
     // Called to notify that IME candidate window has changed its visibility or
     // its appearance. These calls correspond to trigger
     // candidatewindow{show,update,hide} events defined in W3C IME API.
-    virtual void didShowCandidateWindow() { }
-    virtual void didUpdateCandidateWindow() { }
-    virtual void didHideCandidateWindow() { }
-
-    // Returns the text direction at the start and end bounds of the current selection.
-    // If the selection range is empty, it returns false.
-    virtual bool selectionTextDirection(WebTextDirection& start, WebTextDirection& end) const { return false; }
-
-    // Returns true if the selection range is nonempty and its anchor is first
-    // (i.e its anchor is its start).
-    virtual bool isSelectionAnchorFirst() const { return false; }
-
-    // Fetch the current selection range of this WebWidget. If there is no
-    // selection, it will output a 0-length range with the location at the
-    // caret. Returns true and fills the out-paramters on success; returns false
-    // on failure.
-    virtual bool caretOrSelectionRange(size_t* location, size_t* length) { return false; }
-
-    // Changes the text direction of the selected input node.
-    virtual void setTextDirection(WebTextDirection) { }
-
-    // Calling WebWidgetClient::requestPointerLock() will result in one
-    // return call to didAcquirePointerLock() or didNotAcquirePointerLock().
-    virtual void didAcquirePointerLock() { }
-    virtual void didNotAcquirePointerLock() { }
-
-    // Pointer lock was held, but has been lost. This may be due to a
-    // request via WebWidgetClient::requestPointerUnlock(), or for other
-    // reasons such as the user exiting lock, window focus changing, etc.
-    virtual void didLosePointerLock() { }
+    virtual void didShowCandidateWindow() = 0;
+    virtual void didUpdateCandidateWindow() = 0;
+    virtual void didHideCandidateWindow() = 0;
 
     // The page background color. Can be used for filling in areas without
     // content.
-    virtual WebColor backgroundColor() const { return 0xFFFFFFFF; /* SK_ColorWHITE */ }
+    virtual WebColor backgroundColor() const = 0;
 
 protected:
     ~WebWidget() { }