[ios] Removes DCHECKs from GoogleTestRunner.

DCHECKs crash the running XCTest without producing any useful log
output.  Instead, switch to XCTAssertTrue() so that an error message
will be displayed when bots are misconfigured.

BUG=1002739

Change-Id: If902ea15e2b89090fcd355ad7bfb04828e71561a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1799082
Commit-Queue: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Justin Cohen <justincohen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695773}

base/test/ios/google_test_runner.mm

@@ -5,7 +5,6 @@
 #import <UIKit/UIKit.h>
 #import <XCTest/XCTest.h>
 
-#include "base/logging.h"
 #import "base/test/ios/google_test_runner_delegate.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
@@ -18,12 +17,15 @@
 @implementation GoogleTestRunner
 
 - (void)testRunGoogleTests {
+  self.continueAfterFailure = false;
+
   id appDelegate = UIApplication.sharedApplication.delegate;
-  DCHECK([appDelegate conformsToProtocol:@protocol(GoogleTestRunnerDelegate)]);
+  XCTAssertTrue(
+      [appDelegate conformsToProtocol:@protocol(GoogleTestRunnerDelegate)]);
 
   id<GoogleTestRunnerDelegate> runnerDelegate =
       static_cast<id<GoogleTestRunnerDelegate>>(appDelegate);
-  DCHECK(runnerDelegate.supportsRunningGoogleTests);
+  XCTAssertTrue(runnerDelegate.supportsRunningGoogleTests);
   XCTAssertTrue([runnerDelegate runGoogleTests] == 0);
 }