Update paths in sky_home.dart

I also removed the leading /, so it is now possible
to use shelldb start sky/sky_home to test.

Also fixed touch_demo.dart and sector layout to
work and not crash.

R=ianh@google.com

Review URL: https://codereview.chromium.org/1177343002.

examples/rendering/touch_demo.dart

@@ -4,18 +4,22 @@
 
 import 'dart:math';
 import 'dart:sky';
+
 import 'package:sky/framework/app.dart';
 import 'package:sky/framework/rendering/box.dart';
 import 'package:sky/framework/rendering/object.dart';
+import 'package:sky/framework/rendering/paragraph.dart';
+import 'package:sky/framework/rendering/stack.dart';
+import 'package:sky/framework/theme2/colors.dart';
 
 // Material design colors. :p
-List<int> colors = [
-  0xFF009688,
-  0xFFFFC107,
-  0xFF9C27B0,
-  0xFF03A9F4,
-  0xFF673AB7,
-  0xFFCDDC39,
+List<Color> colors = [
+  Teal[500],
+  Amber[500],
+  Purple[500],
+  LightBlue[500],
+  DeepPurple[500],
+  Lime[500],
 ];
 
 class Dot {
@@ -24,7 +28,7 @@ class Dot {
   double y = 0.0;
   double radius = 0.0;
 
-  Dot({int color}) : _paint = new Paint()..color = color;
+  Dot({ Color color }) : _paint = new Paint()..color = color;
 
   void update(PointerEvent event) {
     x = event.x;
@@ -45,7 +49,7 @@ class RenderTouchDemo extends RenderBox {
   void handleEvent(Event event, BoxHitTestEntry entry) {
     switch (event.type) {
       case 'pointerdown':
-        int color = colors[event.pointer.remainder(colors.length)];
+        Color color = colors[event.pointer.remainder(colors.length)];
         dots[event.pointer] = new Dot(color: color)..update(event);
         break;
       case 'pointerup':
@@ -66,14 +70,23 @@ class RenderTouchDemo extends RenderBox {
   }
 
   void paint(RenderObjectDisplayList canvas) {
-    dots.forEach((_, Dot dot) {
+    Paint white = new Paint()..color = const Color(0xFFFFFFFF);
+    canvas.drawRect(new Rect.fromSize(size), white);
+    for (Dot dot in dots.values)
       dot.paint(canvas);
-    });
   }
 }
 
 AppView app;
 
 void main() {
-  app = new AppView(new RenderTouchDemo());
+  var para = new RenderParagraph(text: "Touch me!");
+  var stack = new RenderStack(children: [
+    new RenderTouchDemo(),
+    para,
+  ]);
+  // Make the paragraph not fill the whole screen so it doesn't eat events.
+  para.parentData..top = 40.0
+                 ..left = 20.0;
+  app = new AppView(stack);
 }