| Index: content/public/test/test_utils.h
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| diff --git a/content/public/test/test_utils.h b/content/public/test/test_utils.h
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| index 330210f929b218833e688f1f30e1fac6e5d33a7b..7ca3cf7b47f6eccaf8da51ffb4fb4daea86ddcd3 100644
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| --- a/content/public/test/test_utils.h
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| +++ b/content/public/test/test_utils.h
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| @@ -6,6 +6,7 @@
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|  #define CONTENT_PUBLIC_TEST_TEST_UTILS_H_
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|  
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|  #include <memory>
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| +#include <string>
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|  
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|  #include "base/callback.h"
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|  #include "base/macros.h"
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| @@ -99,6 +100,11 @@ void EnableFeatureWithParam(const base::Feature& feature,
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|                              const std::string& param_value,
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|                              base::CommandLine* command_line);
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|  
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| +// Mutates |command_line| to enable a testing mode for TopDocumentIsolation by
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| +// 1) enabling the features::kTopDocumentIsolation feature and 2) forcing a mode
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| +// that isolates all cross-site frames.
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| +void EnableTopDocumentIsolationForTesting(base::CommandLine* command_line);
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| +
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|  #if defined(OS_ANDROID)
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|  // Registers content/browser JNI bindings necessary for some types of tests.
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|  bool RegisterJniForTesting(JNIEnv* env);
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| @@ -125,7 +131,7 @@ class MessageLoopRunner : public base::RefCountedThreadSafe<MessageLoopRunner> {
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|      DEFERRED,
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|    };
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|  
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| -  MessageLoopRunner(QuitMode mode = QuitMode::DEFERRED);
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| +  explicit MessageLoopRunner(QuitMode mode = QuitMode::DEFERRED);
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|  
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|    // Run the current MessageLoop unless the quit closure
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|    // has already been called.
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| @@ -287,7 +293,7 @@ class InProcessUtilityThreadHelper : public BrowserChildProcessObserver {
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|  // accessing it and causing use-after-free condition.
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|  class RenderFrameDeletedObserver : public WebContentsObserver {
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|   public:
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| -  RenderFrameDeletedObserver(RenderFrameHost* rfh);
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| +  explicit RenderFrameDeletedObserver(RenderFrameHost* rfh);
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|    ~RenderFrameDeletedObserver() override;
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|  
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|    // Overridden WebContentsObserver methods.
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| 
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