Reorganize tests for samples so the test is discoverable from the sample

samples/tests/samples/lib/layout/grid_examples.dart

Index: samples/tests/samples/lib/layout/grid_examples.dart
diff --git a/samples/tests/samples/lib/layout/grid_examples.dart b/samples/tests/samples/lib/layout/grid_examples.dart
deleted file mode 100644
index 3db78c79d390281984067e861df5d30c5dcd2756..0000000000000000000000000000000000000000
--- a/samples/tests/samples/lib/layout/grid_examples.dart
+++ /dev/null
@@ -1,34 +0,0 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-part of layout_tests;
-
-/**
- * The examples from the spec: [http://dev.w3.org/csswg/css3-grid-align/]
- */
-// I've omitted examples that are subsumed by other examples, or examples
-// that illustrate features (such as grid-flow) that are currently
-// unsupported.
-class GridExamples {
-  // Note: controls is positioned in row 3 in the example. Might be a bug in
-  // the example, or they're using flow.
-  // TODO(jmesserly): also needed to set "display: inline-block" to get
-  // horizontal content sizing to work.
-  static const styles = const {
-    '1 Adaptive Layouts': AdaptiveLayout.selectors,
-    '2a Source Independence: Portrait': SourceIndependencePortrait.selectors,
-    '2b Source Independence: Landscape': SourceIndependenceLandscape.selectors,
-    '3 Grid Layering of Elements': GridLayering.selectors,
-    '5 Grid Lines': GridLines_5.selectors,
-    '6 Grid Lines': GridLines_6.selectors,
-    '7 Grid Cells': GridCells.selectors,
-    '11a Starting and Ending Grid Lines': StartEndingGridlines11a.selectors,
-    '11b Starting and Ending Grid Lines': StartEndingGridlines11b.selectors,
-    '12 Repeating Columns and Rows': RepeatingColumnsRows.selectors,
-    '17 Anonymous Grid Cells': AnonymousGridCells.selectors,
-    '20 Implicit Columns and Rows': ImplicitColumnsRows.selectors,
-    '22 Grid Item Alignment': AlignGridItems.selectors,
-    '23 Drawing Order of Grid Items': DrawOrderGridItems.selectors
-  };
-}