Update shelf spacing in Chrome OS according to the MD specs

ash/shelf/app_list_button.cc

Index: ash/shelf/app_list_button.cc
diff --git a/ash/shelf/app_list_button.cc b/ash/shelf/app_list_button.cc
index a57e12378802c6ebd7720ab4f09aae6c80058aa8..e6c06c4e8354cc3030149f53d194aaea136c29d8 100644
--- a/ash/shelf/app_list_button.cc
+++ b/ash/shelf/app_list_button.cc
@@ -5,6 +5,7 @@
 #include "ash/shelf/app_list_button.h"
 
 #include "ash/ash_constants.h"
+#include "ash/material_design/material_design_controller.h"
 #include "ash/shelf/shelf_item_types.h"
 #include "ash/shelf/shelf_layout_manager.h"
 #include "ash/shelf/shelf_view.h"
@@ -31,7 +32,8 @@ AppListButton::AppListButton(ShelfView* shelf_view)
       app_list::switches::IsExperimentalAppListEnabled()
           ? l10n_util::GetStringUTF16(IDS_ASH_SHELF_APP_LIST_LAUNCHER_TITLE)
           : l10n_util::GetStringUTF16(IDS_ASH_SHELF_APP_LIST_TITLE));
-  SetSize(gfx::Size(kShelfSize, kShelfSize));
+  SetSize(gfx::Size(GetShelfLayoutConstant(SHELF_SIZE),
+                    GetShelfLayoutConstant(SHELF_SIZE)));
   SetFocusPainter(views::Painter::CreateSolidFocusPainter(
                       kFocusBorderColor, gfx::Insets(1, 1, 1, 1)));
   set_notify_action(CustomButton::NOTIFY_ON_PRESS);
@@ -125,19 +127,48 @@ void AppListButton::OnPaint(gfx::Canvas* canvas) {
 
   wm::ShelfAlignment alignment = shelf_view_->shelf()->alignment();
   background_bounds.set_size(background_image->size());
-  if (alignment == wm::SHELF_ALIGNMENT_LEFT) {
-    background_bounds.set_x(contents_bounds.width() -
-        ShelfLayoutManager::kShelfItemInset - background_image->width());
-    background_bounds.set_y(contents_bounds.y() +
-        (contents_bounds.height() - background_image->height()) / 2);
-  } else if (alignment == wm::SHELF_ALIGNMENT_RIGHT) {
-    background_bounds.set_x(ShelfLayoutManager::kShelfItemInset);
-    background_bounds.set_y(contents_bounds.y() +
-        (contents_bounds.height() - background_image->height()) / 2);
+
+  // If Material Design for Chrome OS shelf is enabled.
+  if (MaterialDesignController::IsShelfMaterial()) {
+    if (alignment == wm::SHELF_ALIGNMENT_LEFT ||
+        alignment == wm::SHELF_ALIGNMENT_RIGHT) {
+      background_bounds.set_x(
+          (contents_bounds.width() - background_image->width()) / 2);
+      background_bounds.set_y(
+          contents_bounds.y() + ShelfLayoutManager::GetShelfItemInset(
+                                    ShelfLayoutManager::SHELF_ITEM_INSET) +
+          (contents_bounds.height() - background_image->height()) / 2);
+    } else {  // SHELF_ALIGNMENT_BOTTOM
+      background_bounds.set_y(
+          (contents_bounds.height() - background_image->height()) / 2);
+      background_bounds.set_x(
+          contents_bounds.x() +
+          (contents_bounds.width() - background_image->width()) / 2 +
+          ShelfLayoutManager::GetShelfItemInset(
+              ShelfLayoutManager::SHELF_ITEM_INSET));
+    }
   } else {
-    background_bounds.set_y(ShelfLayoutManager::kShelfItemInset);
-    background_bounds.set_x(contents_bounds.x() +
-        (contents_bounds.width() - background_image->width()) / 2);
+    if (alignment == wm::SHELF_ALIGNMENT_LEFT) {
+      background_bounds.set_x(contents_bounds.width() -
+                              ShelfLayoutManager::GetShelfItemInset(
+                                  ShelfLayoutManager::SHELF_ITEM_INSET) -
+                              background_image->width());
+      background_bounds.set_y(
+          contents_bounds.y() +
+          (contents_bounds.height() - background_image->height()) / 2);
+    } else if (alignment == wm::SHELF_ALIGNMENT_RIGHT) {
+      background_bounds.set_x(ShelfLayoutManager::GetShelfItemInset(
+          ShelfLayoutManager::SHELF_ITEM_INSET));
+      background_bounds.set_y(
+          contents_bounds.y() +
+          (contents_bounds.height() - background_image->height()) / 2);
+    } else {  // SHELF_ALIGNMENT_BOTTOM
+      background_bounds.set_y(ShelfLayoutManager::GetShelfItemInset(
+          ShelfLayoutManager::SHELF_ITEM_INSET));
+      background_bounds.set_x(
+          contents_bounds.x() +
+          (contents_bounds.width() - background_image->width()) / 2);
+    }
   }
 
   forground_bounds.set_size(forground_image->size());