Add VR workaround for 819021

Changes the pixel-checking portion of testRequestPresentEntersVr and
testRequestSessionEntersVr to pass if either pure blue or (0, 0, 127) is
detected. This is a workaround for https://crbug.com/819021, where the
immersive mode popup can cause the screen to be darkened and turn pure
blue into (0, 0, 127).

Bug: 819021
Change-Id: Id0254358e7c25073d0b7800cecad8ef11f315c58
Reviewed-on: https://chromium-review.googlesource.com/950321Reviewed-by: Michael Thiessen <mthiesse@chromium.org>
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541143}

chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/WebVrTransitionTest.java

@@ -129,17 +129,21 @@ public class WebVrTransitionTest {
         CriteriaHelper.pollInstrumentationThread(new Criteria() {
             @Override
             public boolean isSatisfied() {
-                Bitmap bmpCurrentScreen = InstrumentationRegistry.getInstrumentation()
-                                                  .getUiAutomation()
-                                                  .takeScreenshot();
+                Bitmap screenshot = InstrumentationRegistry.getInstrumentation()
+                                            .getUiAutomation()
+                                            .takeScreenshot();
 
-                if (bmpCurrentScreen != null) {
+                if (screenshot != null) {
                     // Calculate center of eye coordinates.
-                    int iheight = uiDevice.getDisplayHeight() / 2;
-                    int iwidth = uiDevice.getDisplayWidth() / 4;
+                    int height = uiDevice.getDisplayHeight() / 2;
+                    int width = uiDevice.getDisplayWidth() / 4;
 
                     // Verify screen is blue.
-                    return Color.BLUE == bmpCurrentScreen.getPixel(iwidth, iheight);
+                    int pixel = screenshot.getPixel(width, height);
+                    // Workaround for the immersive mode popup sometimes being rendered over the
+                    // screen on K, which causes the pure blue to be darkened to (0, 0, 127).
+                    // TODO(https://crbug.com/819021): Only check pure blue.
+                    return pixel == Color.BLUE || pixel == Color.rgb(0, 0, 127);
                 }
                 return false;
             }