Add extension API to change window show state using chrome.windows.update().

chrome/test/data/extensions/api_test/window_update/show_state/test.html

+<script>
+var pass = chrome.test.callbackPass;
+
+var width = 0;
+var height = 0;
+var changedWidth = 500;
+var changedHeight = 500;
+
+function checkRestoreWithBounds(theWindow) {
+  chrome.test.assertEq('normal', theWindow.state);
+  if (theWindow.type == 'panel') {
+    // Panels decide their own bounds.
+    chrome.test.assertEq(width, theWindow.width);
+    chrome.test.assertEq(height, theWindow.height);
+  } else {
+    chrome.test.assertEq(changedWidth, theWindow.width);
+    chrome.test.assertEq(changedHeight, theWindow.height);
+  }
+
+  chrome.windows.remove(theWindow.id, pass());
+}
+
+function checkMaximized(theWindow) {
+  if (theWindow.type == 'panel') {
+    // Maximize is the same as restore for panels.
+    chrome.test.assertEq('normal', theWindow.state);
+    chrome.test.assertEq(width, theWindow.width);
+    chrome.test.assertEq(height, theWindow.height);
+  } else {
+    chrome.test.assertEq('maximized', theWindow.state);
+    chrome.test.assertTrue(width < theWindow.width ||
+                           height < theWindow.height);
+  }
+
+  chrome.windows.update(theWindow.id,
+      {'state': 'normal', width: changedWidth, height: changedHeight},
+      pass(checkRestoreWithBounds));
+}
+
+function checkRestored(theWindow) {
+  chrome.test.assertEq('normal', theWindow.state);
+  chrome.test.assertEq(width, theWindow.width);
+  chrome.test.assertEq(height, theWindow.height);
+
+  chrome.windows.update(theWindow.id, {'state': 'maximized'}, pass(checkMaximized));
+}
+
+function checkMinimized(theWindow) {
+  chrome.test.assertEq('minimized', theWindow.state);
+  chrome.windows.update(theWindow.id, {'state': 'normal'}, pass(checkRestored));
+}
+
+function minimizeWindow(theWindow) {
+  chrome.test.assertEq('normal', theWindow.state);
+  width = theWindow.width;
+  height = theWindow.height;
+  chrome.windows.update(theWindow.id, {'state': 'minimized'}, pass(checkMinimized));
+}
+
+function testWindowState(windowType) {
+  chrome.windows.create({'url': 'hello.html', 'type': windowType},
+    pass(minimizeWindow));
+}
+
+chrome.test.runTests([
+  function changeWindowState() {
+    testWindowState('normal');
+  },
+  function changePopupWindowState() {
+    testWindowState('popup');
+  },
+  function changePanelWindowState() {
+    testWindowState('panel');
+  }
+]);
+</script>