Hide overlay play button if it can't be shown without clipping

third_party/WebKit/LayoutTests/virtual/android/media/controls/overlay-play-button.js

+// Defined in core/html/shadow/MediaControls.cpp.
+var MIN_VIDEO_WIDTH = 48;
+var MIN_VIDEO_HEIGHT = 164;
+
+function assertOverlayPlayButtonVisible(videoElement) {
+  assert_true(isVisible(overlayPlayButton(videoElement)),
+      "overlay play button should be visible");
+}
+
+function assertOverlayPlayButtonNotVisible(videoElement) {
+  assert_false(isVisible(overlayPlayButton(videoElement)),
+      "overlay play button should not be visible");
+}
+
+function overlayPlayButton(videoElement) {
+  var controlID = '-webkit-media-controls-overlay-play-button';
+  var button = mediaControlsElement(
+      window.internals.shadowRoot(videoElement).firstChild,
+      controlID);
+  if (!button)
+    throw 'Failed to find overlay play button';
+  return button;
+}
+
+function isVisible(button) {
+    var computedStyle = getComputedStyle(button);
+    return computedStyle.display !== "none" &&
+           computedStyle.display !== "hidden" &&
+           computedStyle.visibility === "visible";
+}