Further decrease rate of VR content clicks

Further decreases the rate at which clicks are sent to content nodes
during instrumentation tests for the VR browser to ensure that all
clicks are reliably picked up.

Bug: 953990
Change-Id: I6f903f14f2a6bb02fef7e7a76629fa5e038e2e55
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1601414
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Commit-Queue: Klaus Weidner <klausw@chromium.org>
Auto-Submit: Brian Sheedy <bsheedy@chromium.org>
Reviewed-by: Klaus Weidner <klausw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#657764}

chrome/android/javatests/src/org/chromium/chrome/browser/vr/util/NativeUiUtils.java

@@ -219,11 +219,13 @@ public class NativeUiUtils {
             for (int i = 0; i < numClicks; ++i) {
                 clickElement(UserFriendlyElementName.CONTENT_QUAD, clickCoordinates);
                 // Rarely, sending clicks back to back can cause the web contents to miss a click.
-                // So, if we're going to be sending more, introduce a couple of input-less frames
-                // to avoid this issue.
+                // So, if we're going to be sending more, introduce a few input-less frames to avoid
+                // this issue. 3 appears to currently be the magic number that lets the web contents
+                // reliably pick up all clicks.
                 if (i < numClicks - 1) {
-                    hoverElement(UserFriendlyElementName.CONTENT_QUAD, clickCoordinates);
-                    hoverElement(UserFriendlyElementName.CONTENT_QUAD, clickCoordinates);
+                    for (int j = 0; j < 3; ++j) {
+                        hoverElement(UserFriendlyElementName.CONTENT_QUAD, clickCoordinates);
+                    }
                 }
             }
         });