Add Flex to views::BoxLayout.

ui/views/layout/box_layout_unittest.cc

Index: ui/views/layout/box_layout_unittest.cc
diff --git a/ui/views/layout/box_layout_unittest.cc b/ui/views/layout/box_layout_unittest.cc
index 5f58b15c8fd173afb7638ed94db7aab133a22ba0..85b54f47d8b440e4e1a915dcba420ba061d84dbe 100644
--- a/ui/views/layout/box_layout_unittest.cc
+++ b/ui/views/layout/box_layout_unittest.cc
@@ -19,78 +19,83 @@ class BoxLayoutTest : public testing::Test {
   }
 
   scoped_ptr<View> host_;
-  scoped_ptr<BoxLayout> layout_;
 };
 
 }  // namespace
 
 TEST_F(BoxLayoutTest, Empty) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 10, 10, 20));
-  EXPECT_EQ(gfx::Size(20, 20), layout_->GetPreferredSize(host_.get()));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 10, 10, 20);
+  host_->SetLayoutManager(layout);
+  EXPECT_EQ(gfx::Size(20, 20), layout->GetPreferredSize(host_.get()));
 }
 
 TEST_F(BoxLayoutTest, AlignmentHorizontal) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 0, 0, 0));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 0, 0, 0);
+  host_->SetLayoutManager(layout);
   View* v1 = new StaticSizedView(gfx::Size(10, 20));
   host_->AddChildView(v1);
   View* v2 = new StaticSizedView(gfx::Size(10, 10));
   host_->AddChildView(v2);
-  EXPECT_EQ(gfx::Size(20, 20), layout_->GetPreferredSize(host_.get()));
+  EXPECT_EQ(gfx::Size(20, 20), layout->GetPreferredSize(host_.get()));
   host_->SetBounds(0, 0, 20, 20);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 10, 20), v1->bounds());
   EXPECT_EQ(gfx::Rect(10, 0, 10, 20), v2->bounds());
 }
 
 TEST_F(BoxLayoutTest, AlignmentVertical) {
-  layout_.reset(new BoxLayout(BoxLayout::kVertical, 0, 0, 0));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kVertical, 0, 0, 0);
+  host_->SetLayoutManager(layout);
   View* v1 = new StaticSizedView(gfx::Size(20, 10));
   host_->AddChildView(v1);
   View* v2 = new StaticSizedView(gfx::Size(10, 10));
   host_->AddChildView(v2);
-  EXPECT_EQ(gfx::Size(20, 20), layout_->GetPreferredSize(host_.get()));
+  EXPECT_EQ(gfx::Size(20, 20), layout->GetPreferredSize(host_.get()));
   host_->SetBounds(0, 0, 20, 20);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 20, 10), v1->bounds());
   EXPECT_EQ(gfx::Rect(0, 10, 20, 10), v2->bounds());
 }
 
 TEST_F(BoxLayoutTest, SetInsideBorderInsets) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 10, 20, 0));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 10, 20, 0);
+  host_->SetLayoutManager(layout);
   View* v1 = new StaticSizedView(gfx::Size(10, 20));
   host_->AddChildView(v1);
   View* v2 = new StaticSizedView(gfx::Size(10, 10));
   host_->AddChildView(v2);
-  EXPECT_EQ(gfx::Size(40, 60), layout_->GetPreferredSize(host_.get()));
+  EXPECT_EQ(gfx::Size(40, 60), layout->GetPreferredSize(host_.get()));
   host_->SetBounds(0, 0, 40, 60);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 20, 10, 20), v1->bounds());
   EXPECT_EQ(gfx::Rect(20, 20, 10, 20), v2->bounds());
 
-  layout_->set_inside_border_insets(
+  layout->set_inside_border_insets(
       gfx::Insets(5, 10, 15, 20));
-  EXPECT_EQ(gfx::Size(50, 40), layout_->GetPreferredSize(host_.get()));
+  EXPECT_EQ(gfx::Size(50, 40), layout->GetPreferredSize(host_.get()));
   host_->SetBounds(0, 0, 50, 40);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 5, 10, 20), v1->bounds());
   EXPECT_EQ(gfx::Rect(20, 5, 10, 20), v2->bounds());
 }
 
 TEST_F(BoxLayoutTest, Spacing) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 7, 7, 8));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 7, 7, 8);
+  host_->SetLayoutManager(layout);
   View* v1 = new StaticSizedView(gfx::Size(10, 20));
   host_->AddChildView(v1);
   View* v2 = new StaticSizedView(gfx::Size(10, 20));
   host_->AddChildView(v2);
-  EXPECT_EQ(gfx::Size(42, 34), layout_->GetPreferredSize(host_.get()));
+  EXPECT_EQ(gfx::Size(42, 34), layout->GetPreferredSize(host_.get()));
   host_->SetBounds(0, 0, 100, 100);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(7, 7, 10, 86), v1->bounds());
   EXPECT_EQ(gfx::Rect(25, 7, 10, 86), v2->bounds());
 }
 
 TEST_F(BoxLayoutTest, Overflow) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 0, 0, 0));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 0, 0, 0);
+  host_->SetLayoutManager(layout);
   View* v1 = new StaticSizedView(gfx::Size(20, 20));
   host_->AddChildView(v1);
   View* v2 = new StaticSizedView(gfx::Size(10, 20));
@@ -99,92 +104,79 @@ TEST_F(BoxLayoutTest, Overflow) {
 
   // Overflows by positioning views at the start and truncating anything that
   // doesn't fit.
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 10, 10), v1->bounds());
   EXPECT_EQ(gfx::Rect(0, 0, 0, 0), v2->bounds());
 
   // All values of main axis alignment should overflow in the same manner.
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 10, 10), v1->bounds());
   EXPECT_EQ(gfx::Rect(0, 0, 0, 0), v2->bounds());
 
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 10, 10), v1->bounds());
   EXPECT_EQ(gfx::Rect(0, 0, 0, 0), v2->bounds());
 
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 10, 10), v1->bounds());
   EXPECT_EQ(gfx::Rect(0, 0, 0, 0), v2->bounds());
 }
 
 TEST_F(BoxLayoutTest, NoSpace) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10);
+  host_->SetLayoutManager(layout);
   View* childView = new StaticSizedView(gfx::Size(20, 20));
   host_->AddChildView(childView);
   host_->SetBounds(0, 0, 10, 10);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 0, 0), childView->bounds());
 }
 
 TEST_F(BoxLayoutTest, InvisibleChild) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10);
+  host_->SetLayoutManager(layout);
   View* v1 = new StaticSizedView(gfx::Size(20, 20));
   v1->SetVisible(false);
   host_->AddChildView(v1);
   View* v2 = new StaticSizedView(gfx::Size(10, 10));
   host_->AddChildView(v2);
-  EXPECT_EQ(gfx::Size(30, 30), layout_->GetPreferredSize(host_.get()));
+  EXPECT_EQ(gfx::Size(30, 30), layout->GetPreferredSize(host_.get()));
   host_->SetBounds(0, 0, 30, 30);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 10, 10), v2->bounds());
 }
 
-TEST_F(BoxLayoutTest, MainAxisAlignmentFill) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10));
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_FILL);
-
-  View* v1 = new StaticSizedView(gfx::Size(20, 20));
-  host_->AddChildView(v1);
-  View* v2 = new StaticSizedView(gfx::Size(10, 10));
-  host_->AddChildView(v2);
-  EXPECT_EQ(gfx::Size(60, 40), layout_->GetPreferredSize(host_.get()));
-
-  host_->SetBounds(0, 0, 100, 40);
-  layout_->Layout(host_.get());
-  EXPECT_EQ(gfx::Rect(10, 10, 40, 20).ToString(), v1->bounds().ToString());
-  EXPECT_EQ(gfx::Rect(60, 10, 30, 20).ToString(), v2->bounds().ToString());
-}
-
 TEST_F(BoxLayoutTest, UseHeightForWidth) {
-  layout_.reset(new BoxLayout(BoxLayout::kVertical, 0, 0, 0));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kVertical, 0, 0, 0);
+  host_->SetLayoutManager(layout);
   View* v1 = new StaticSizedView(gfx::Size(20, 10));
   host_->AddChildView(v1);
   ProportionallySizedView* v2 = new ProportionallySizedView(2);
   v2->set_preferred_width(10);
   host_->AddChildView(v2);
-  EXPECT_EQ(gfx::Size(20, 50), layout_->GetPreferredSize(host_.get()));
+  EXPECT_EQ(gfx::Size(20, 50), layout->GetPreferredSize(host_.get()));
 
   host_->SetBounds(0, 0, 20, 50);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 20, 10), v1->bounds());
   EXPECT_EQ(gfx::Rect(0, 10, 20, 40), v2->bounds());
 
-  EXPECT_EQ(110, layout_->GetPreferredHeightForWidth(host_.get(), 50));
+  EXPECT_EQ(110, layout->GetPreferredHeightForWidth(host_.get(), 50));
 
   // Test without horizontal stretching of the views.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_END);
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_END);
   EXPECT_EQ(gfx::Size(20, 30).ToString(),
-            layout_->GetPreferredSize(host_.get()).ToString());
+            layout->GetPreferredSize(host_.get()).ToString());
 
   host_->SetBounds(0, 0, 20, 30);
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(0, 0, 20, 10), v1->bounds());
   EXPECT_EQ(gfx::Rect(10, 10, 10, 20), v2->bounds());
 
-  EXPECT_EQ(30, layout_->GetPreferredHeightForWidth(host_.get(), 50));
+  EXPECT_EQ(30, layout->GetPreferredHeightForWidth(host_.get(), 50));
 }
 
 TEST_F(BoxLayoutTest, EmptyPreferredSize) {
@@ -210,7 +202,8 @@ TEST_F(BoxLayoutTest, EmptyPreferredSize) {
 }
 
 TEST_F(BoxLayoutTest, MainAxisAlignmentHorizontal) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10);
+  host_->SetLayoutManager(layout);
 
   View* v1 = new StaticSizedView(gfx::Size(20, 20));
   host_->AddChildView(v1);
@@ -220,32 +213,33 @@ TEST_F(BoxLayoutTest, MainAxisAlignmentHorizontal) {
   host_->SetBounds(0, 0, 100, 40);
 
   // Align children to the horizontal start by default.
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(40, 10, 10, 20).ToString(), v2->bounds().ToString());
 
   // Ensure same results for MAIN_AXIS_ALIGNMENT_START.
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(40, 10, 10, 20).ToString(), v2->bounds().ToString());
 
   // Aligns children to the center horizontally.
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(30, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(60, 10, 10, 20).ToString(), v2->bounds().ToString());
 
   // Aligns children to the end of the host horizontally, accounting for the
   // inside border spacing.
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(50, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(80, 10, 10, 20).ToString(), v2->bounds().ToString());
 }
 
 TEST_F(BoxLayoutTest, MainAxisAlignmentVertical) {
-  layout_.reset(new BoxLayout(BoxLayout::kVertical, 10, 10, 10));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kVertical, 10, 10, 10);
+  host_->SetLayoutManager(layout);
 
   View* v1 = new StaticSizedView(gfx::Size(20, 20));
   host_->AddChildView(v1);
@@ -255,32 +249,33 @@ TEST_F(BoxLayoutTest, MainAxisAlignmentVertical) {
   host_->SetBounds(0, 0, 40, 100);
 
   // Align children to the vertical start by default.
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(10, 40, 20, 10).ToString(), v2->bounds().ToString());
 
   // Ensure same results for MAIN_AXIS_ALIGNMENT_START.
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(10, 40, 20, 10).ToString(), v2->bounds().ToString());
 
   // Aligns children to the center vertically.
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 30, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(10, 60, 20, 10).ToString(), v2->bounds().ToString());
 
   // Aligns children to the end of the host vertically, accounting for the
   // inside border spacing.
-  layout_->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
-  layout_->Layout(host_.get());
+  layout->set_main_axis_alignment(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 50, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(10, 80, 20, 10).ToString(), v2->bounds().ToString());
 }
 
 TEST_F(BoxLayoutTest, CrossAxisAlignmentHorizontal) {
-  layout_.reset(new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10);
+  host_->SetLayoutManager(layout);
 
   View* v1 = new StaticSizedView(gfx::Size(20, 20));
   host_->AddChildView(v1);
@@ -290,38 +285,39 @@ TEST_F(BoxLayoutTest, CrossAxisAlignmentHorizontal) {
   host_->SetBounds(0, 0, 100, 60);
 
   // Stretch children to fill the available height by default.
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 20, 40).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(40, 10, 10, 40).ToString(), v2->bounds().ToString());
 
   // Ensure same results for CROSS_AXIS_ALIGNMENT_STRETCH.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_STRETCH);
-  layout_->Layout(host_.get());
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_STRETCH);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 20, 40).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(40, 10, 10, 40).ToString(), v2->bounds().ToString());
 
   // Aligns children to the start vertically.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_START);
-  layout_->Layout(host_.get());
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_START);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(40, 10, 10, 10).ToString(), v2->bounds().ToString());
 
   // Aligns children to the center vertically.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_CENTER);
-  layout_->Layout(host_.get());
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_CENTER);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 20, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(40, 25, 10, 10).ToString(), v2->bounds().ToString());
 
   // Aligns children to the end of the host vertically, accounting for the
   // inside border spacing.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_END);
-  layout_->Layout(host_.get());
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_END);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 30, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(40, 40, 10, 10).ToString(), v2->bounds().ToString());
 }
 
 TEST_F(BoxLayoutTest, CrossAxisAlignmentVertical) {
-  layout_.reset(new BoxLayout(BoxLayout::kVertical, 10, 10, 10));
+  BoxLayout* layout = new BoxLayout(BoxLayout::kVertical, 10, 10, 10);
+  host_->SetLayoutManager(layout);
 
   View* v1 = new StaticSizedView(gfx::Size(20, 20));
   host_->AddChildView(v1);
@@ -331,34 +327,267 @@ TEST_F(BoxLayoutTest, CrossAxisAlignmentVertical) {
   host_->SetBounds(0, 0, 60, 100);
 
   // Stretch children to fill the available width by default.
-  layout_->Layout(host_.get());
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 40, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(10, 40, 40, 10).ToString(), v2->bounds().ToString());
 
   // Ensure same results for CROSS_AXIS_ALIGNMENT_STRETCH.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_STRETCH);
-  layout_->Layout(host_.get());
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_STRETCH);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 40, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(10, 40, 40, 10).ToString(), v2->bounds().ToString());
 
   // Aligns children to the start horizontally.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_START);
-  layout_->Layout(host_.get());
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_START);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(10, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(10, 40, 10, 10).ToString(), v2->bounds().ToString());
 
   // Aligns children to the center horizontally.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_CENTER);
-  layout_->Layout(host_.get());
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_CENTER);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(20, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(25, 40, 10, 10).ToString(), v2->bounds().ToString());
 
   // Aligns children to the end of the host horizontally, accounting for the
   // inside border spacing.
-  layout_->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_END);
-  layout_->Layout(host_.get());
+  layout->set_cross_axis_alignment(BoxLayout::CROSS_AXIS_ALIGNMENT_END);
+  host_->Layout();
   EXPECT_EQ(gfx::Rect(30, 10, 20, 20).ToString(), v1->bounds().ToString());
   EXPECT_EQ(gfx::Rect(40, 40, 10, 10).ToString(), v2->bounds().ToString());
 }
 
+TEST_F(BoxLayoutTest, FlexAll) {
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10);
+  host_->SetLayoutManager(layout);
+  layout->SetDefaultFlex(1);
+
+  View* v1 = new StaticSizedView(gfx::Size(20, 20));
+  host_->AddChildView(v1);
+  View* v2 = new StaticSizedView(gfx::Size(10, 10));
+  host_->AddChildView(v2);
+  View* v3 = new StaticSizedView(gfx::Size(30, 30));
+  host_->AddChildView(v3);
+  EXPECT_EQ(gfx::Size(100, 50), layout->GetPreferredSize(host_.get()));
+
+  host_->SetBounds(0, 0, 120, 50);
+  host_->Layout();
+  EXPECT_EQ(gfx::Rect(10, 10, 27, 30).ToString(), v1->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(47, 10, 16, 30).ToString(), v2->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(73, 10, 37, 30).ToString(), v3->bounds().ToString());
+}
+
+TEST_F(BoxLayoutTest, FlexGrowVertical) {
+  BoxLayout* layout = new BoxLayout(BoxLayout::kVertical, 10, 10, 10);
+  host_->SetLayoutManager(layout);
+
+  View* v1 = new StaticSizedView(gfx::Size(20, 20));
+  host_->AddChildView(v1);
+  View* v2 = new StaticSizedView(gfx::Size(10, 10));
+  host_->AddChildView(v2);
+  View* v3 = new StaticSizedView(gfx::Size(30, 30));
+  host_->AddChildView(v3);
+
+  host_->SetBounds(0, 0, 50, 130);
+
+  // Views don't fill the available space by default.
+  host_->Layout();
+  EXPECT_EQ(gfx::Rect(10, 10, 30, 20).ToString(), v1->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(10, 40, 30, 10).ToString(), v2->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(10, 60, 30, 30).ToString(), v3->bounds().ToString());
+
+  std::vector<BoxLayout::MainAxisAlignment> main_alignments;
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
+
+  for (size_t i = 0; i < main_alignments.size(); ++i) {
+    layout->set_main_axis_alignment(main_alignments[i]);
+
+    // Set the first view to consume all free space.
+    layout->SetFlexForView(v1, 1);
+    layout->ClearFlexForView(v2);
+    layout->ClearFlexForView(v3);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(10, 10, 30, 50).ToString(), v1->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(10, 70, 30, 10).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(10, 90, 30, 30).ToString(), v3->bounds().ToString());
+
+    // Set the third view to take 2/3s of the free space and leave the first
+    // view
+    // with 1/3.
+    layout->SetFlexForView(v3, 2);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(10, 10, 30, 30).ToString(), v1->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(10, 50, 30, 10).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(10, 70, 30, 50).ToString(), v3->bounds().ToString());
+
+    // Clear the previously set flex values and set the second view to take all
+    // the free space.
+    layout->ClearFlexForView(v1);
+    layout->SetFlexForView(v2, 1);
+    layout->ClearFlexForView(v3);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(10, 10, 30, 20).ToString(), v1->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(10, 40, 30, 40).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(10, 90, 30, 30).ToString(), v3->bounds().ToString());
+  }
+}
+
+TEST_F(BoxLayoutTest, FlexGrowHorizontalWithRemainder) {
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 0, 0, 0);
+  host_->SetLayoutManager(layout);
+  layout->SetDefaultFlex(1);
+  std::vector<View*> views;
+  for (int i = 0; i < 5; ++i) {
+    View* view = new StaticSizedView(gfx::Size(10, 10));
+    views.push_back(view);
+    host_->AddChildView(view);
+  }
+
+  EXPECT_EQ(gfx::Size(50, 10), layout->GetPreferredSize(host_.get()));
+
+  host_->SetBounds(0, 0, 52, 10);
+  host_->Layout();
+  // The 2nd and 4th views should have an extra pixel as they correspond to 20.8
+  // and 41.6 which round up.
+  EXPECT_EQ(gfx::Rect(0, 0, 10, 10).ToString(), views[0]->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(10, 0, 11, 10).ToString(), views[1]->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(21, 0, 10, 10).ToString(), views[2]->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(31, 0, 11, 10).ToString(), views[3]->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(42, 0, 10, 10).ToString(), views[4]->bounds().ToString());
+}
+
+TEST_F(BoxLayoutTest, FlexGrowHorizontalWithRemainder2) {
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 0, 0, 0);
+  host_->SetLayoutManager(layout);
+  layout->SetDefaultFlex(1);
+  std::vector<View*> views;
+  for (int i = 0; i < 4; ++i) {
+    View* view = new StaticSizedView(gfx::Size(1, 10));
+    views.push_back(view);
+    host_->AddChildView(view);
+  }
+
+  EXPECT_EQ(gfx::Size(4, 10), layout->GetPreferredSize(host_.get()));
+
+  host_->SetBounds(0, 0, 10, 10);
+  host_->Layout();
+  // The 1st and 3rd views should have an extra pixel as they correspond to 2.5
+  // and 7.5 which round up.
+  EXPECT_EQ(gfx::Rect(0, 0, 3, 10).ToString(), views[0]->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(3, 0, 2, 10).ToString(), views[1]->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(5, 0, 3, 10).ToString(), views[2]->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(8, 0, 2, 10).ToString(), views[3]->bounds().ToString());
+}
+
+TEST_F(BoxLayoutTest, FlexShrinkHorizontal) {
+  BoxLayout* layout = new BoxLayout(BoxLayout::kHorizontal, 10, 10, 10);
+  host_->SetLayoutManager(layout);
+
+  View* v1 = new StaticSizedView(gfx::Size(20, 20));
+  host_->AddChildView(v1);
+  View* v2 = new StaticSizedView(gfx::Size(10, 10));
+  host_->AddChildView(v2);
+  View* v3 = new StaticSizedView(gfx::Size(30, 30));
+  host_->AddChildView(v3);
+
+  host_->SetBounds(0, 0, 85, 50);
+
+  // Truncate width by default.
+  host_->Layout();
+  EXPECT_EQ(gfx::Rect(10, 10, 20, 30).ToString(), v1->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(40, 10, 10, 30).ToString(), v2->bounds().ToString());
+  EXPECT_EQ(gfx::Rect(60, 10, 15, 30).ToString(), v3->bounds().ToString());
+
+  std::vector<BoxLayout::MainAxisAlignment> main_alignments;
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
+
+  for (size_t i = 0; i < main_alignments.size(); ++i) {
+    layout->set_main_axis_alignment(main_alignments[i]);
+
+    // Set the first view to shrink as much as necessary.
+    layout->SetFlexForView(v1, 1);
+    layout->ClearFlexForView(v2);
+    layout->ClearFlexForView(v3);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(10, 10, 5, 30).ToString(), v1->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(25, 10, 10, 30).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(45, 10, 30, 30).ToString(), v3->bounds().ToString());
+
+    // Set the third view to shrink 2/3s of the free space and leave the first
+    // view with 1/3.
+    layout->SetFlexForView(v3, 2);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(10, 10, 15, 30).ToString(), v1->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(35, 10, 10, 30).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(55, 10, 20, 30).ToString(), v3->bounds().ToString());
+
+    // Clear the previously set flex values and set the second view to take all
+    // the free space with MAIN_AXIS_ALIGNMENT_END set. This causes the second
+    // view to shrink to zero and the third view still doesn't fit so it
+    // overflows.
+    layout->ClearFlexForView(v1);
+    layout->SetFlexForView(v2, 2);
+    layout->ClearFlexForView(v3);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(10, 10, 20, 30).ToString(), v1->bounds().ToString());
+    // Conceptually this view is at 10, 40, 0, 0.
+    EXPECT_EQ(gfx::Rect(0, 0, 0, 0).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(50, 10, 25, 30).ToString(), v3->bounds().ToString());
+  }
+}
+
+TEST_F(BoxLayoutTest, FlexShrinkVerticalWithRemainder) {
+  BoxLayout* layout = new BoxLayout(BoxLayout::kVertical, 0, 0, 0);
+  host_->SetLayoutManager(layout);
+  View* v1 = new StaticSizedView(gfx::Size(20, 10));
+  host_->AddChildView(v1);
+  View* v2 = new StaticSizedView(gfx::Size(20, 20));
+  host_->AddChildView(v2);
+  View* v3 = new StaticSizedView(gfx::Size(20, 10));
+  host_->AddChildView(v3);
+  host_->SetBounds(0, 0, 20, 20);
+
+  std::vector<BoxLayout::MainAxisAlignment> main_alignments;
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_START);
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_CENTER);
+  main_alignments.push_back(BoxLayout::MAIN_AXIS_ALIGNMENT_END);
+
+  for (size_t i = 0; i < main_alignments.size(); ++i) {
+    layout->set_main_axis_alignment(main_alignments[i]);
+
+    // The first view shrinks by 1/3 of the excess, the second view shrinks by
+    // 2/3 of the excess and the third view should maintain its preferred size.
+    layout->SetFlexForView(v1, 1);
+    layout->SetFlexForView(v2, 2);
+    layout->ClearFlexForView(v3);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(0, 0, 20, 3).ToString(), v1->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(0, 3, 20, 7).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(0, 10, 20, 10).ToString(), v3->bounds().ToString());
+
+    // The second view shrinks to 2/3 of the excess, the third view shrinks to
+    // 1/3 of the excess and the first view should maintain its preferred size.
+    layout->ClearFlexForView(v1);
+    layout->SetFlexForView(v2, 2);
+    layout->SetFlexForView(v3, 1);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(0, 0, 20, 10).ToString(), v1->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(0, 10, 20, 7).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(0, 17, 20, 3).ToString(), v3->bounds().ToString());
+
+    // Each view shrinks equally to fit within the available space.
+    layout->SetFlexForView(v1, 1);
+    layout->SetFlexForView(v2, 1);
+    layout->SetFlexForView(v3, 1);
+    host_->Layout();
+    EXPECT_EQ(gfx::Rect(0, 0, 20, 3).ToString(), v1->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(0, 3, 20, 14).ToString(), v2->bounds().ToString());
+    EXPECT_EQ(gfx::Rect(0, 17, 20, 3).ToString(), v3->bounds().ToString());
+  }
+}
+
 }  // namespace views