cast: Fix compile error caused by incompatible use of base::ContainsValue

base::ContainsValue tries to compare the value to the element in
container. Unfortunately for a map, this isn't possible since the
returned element is a pair<>.

Bug: None
Test: Compile cast_shell
Change-Id: I3d072442f7d9e9c895adc934133f626abe104a88
Reviewed-on: https://chromium-review.googlesource.com/c/1354348Reviewed-by: Alex Sakhartchouk <alexst@chromium.org>
Commit-Queue: Daniel Nicoara <dnicoara@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612208}

chromecast/browser/exo/wm_helper_cast_shell.cc

@@ -183,7 +183,7 @@ void WMHelperCastShell::CastDisplayObserver::OnDisplayRemoved(
 void WMHelperCastShell::CastDisplayObserver::OnDisplayMetricsChanged(
     const display::Display& display,
     uint32_t changed_metrics) {
-  if (!base::ContainsValue(display_info_, display.id())) {
+  if (display_info_.find(display.id()) == display_info_.end()) {
     display::ManagedDisplayInfo md(display.id(), "CastDisplayInfo", true);
     md.SetBounds(display.bounds());
     display_info_.emplace(display.id(), md);