Revert of Reland Enable crashpad for Mac. (patchset #1 id:1 of https://codereview.chromium.org/2820453003/ )

Reason for revert:
Sorry, looks like this is still causing some test failures:
https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Fchromium.mac%2FMac10.10_Tests%2F16868%2F%2B%2Frecipes%2Fsteps%2Fheadless_browsertests_on_Mac-10.10%2F0%2Flogs%2FCrashReporterTest.GenerateMinidump%2F0
https://uberchromegw.corp.google.com/i/chromium.mac/builders/Mac10.10%20Tests/builds/16868

Original issue's description:
> Reland Enable crashpad for Mac.
> -- Add :mac_helpers dependendency to headless_lib
>
>
>
> Original reason for revert: Reason for revert:
> mac_chromium10.10_rel_ng buildbot failing in browsertests
> https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Fchromium.mac%2FMac10.10_Tests%2F16541%2F%2B%2Frecipes%2Fsteps%2Fheadless_browsertests_on_Mac-10.10%2F0%2Flogs%2FCrashReporterTest.GenerateMinidump%2F0
>
>
> This follows the same logic as using breakpad in linux with flags --enable_crash-reporter and --crash-dumps-dir folders.
>
> For headless_shell target, we need to include the Helper crashpad_handler in the build. For --headless, this is already available in the framework bundle.
>
> BUG=687407
>
> Review-Url: https://codereview.chromium.org/2816593006
> Cr-Commit-Position: refs/heads/master@{#464289}
> Committed: ecb2ad2495
>
> patch from issue 2816593006 at patchset 60001 (http://crrev.com/2816593006#ps60001)
>
> Review-Url: https://codereview.chromium.org/2820453003
> Cr-Commit-Position: refs/heads/master@{#465869}
> Committed: df51c3e481

TBR=skyostil@chromium.org,dvallet@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=687407

Review-Url: https://codereview.chromium.org/2826193003
Cr-Commit-Position: refs/heads/master@{#465895}

headless/BUILD.gn

@@ -342,9 +342,7 @@ static_library("headless_lib") {
     "//url",
   ]
 
-  if (is_mac) {
-    deps += [ ":mac_helpers" ]
-  } else {
+  if (!is_mac) {
     deps += [ "//ui/aura" ]
   }
 
@@ -434,22 +432,6 @@ repack("headless_browser_tests_pak") {
   ]
 }
 
-if (is_mac) {
-  copy("mac_helpers") {
-    sources = [
-      "$root_out_dir/crashpad_handler",
-    ]
-
-    deps = [
-      "//third_party/crashpad/crashpad/handler:crashpad_handler",
-    ]
-
-    outputs = [
-      "$root_out_dir/Helpers/{{source_file_part}}",
-    ]
-  }
-}
-
 test("headless_browsertests") {
   sources = [
     "lib/embedder_mojo_browsertest.cc",

headless/lib/headless_browser_browsertest.cc

@@ -717,13 +717,12 @@ class CrashReporterTest : public HeadlessBrowserTest,
   base::FilePath crash_dumps_dir_;
 };
 
-// TODO(skyostil): Minidump generation currently is only supported on Linux and
-// Mac.
-#if defined(HEADLESS_USE_BREAKPAD) || defined(OS_MACOSX)
+// TODO(skyostil): Minidump generation currently is only supported on Linux.
+#if defined(HEADLESS_USE_BREAKPAD)
 #define MAYBE_GenerateMinidump GenerateMinidump
 #else
 #define MAYBE_GenerateMinidump DISABLED_GenerateMinidump
-#endif  // defined(HEADLESS_USE_BREAKPAD) || defined(OS_MACOSX)
+#endif  // defined(HEADLESS_USE_BREAKPAD)
 IN_PROC_BROWSER_TEST_F(CrashReporterTest, MAYBE_GenerateMinidump) {
   // Navigates a tab to chrome://crash and checks that a minidump is generated.
   // Note that we only test renderer crashes here -- browser crashes need to be
@@ -745,10 +744,6 @@ IN_PROC_BROWSER_TEST_F(CrashReporterTest, MAYBE_GenerateMinidump) {
 
   // Check that one minidump got created.
   {
-#if defined(OS_MACOSX)
-    // Mac outputs dumps in the 'completed' directory.
-    crash_dumps_dir_ = crash_dumps_dir_.Append("completed");
-#endif
     base::ThreadRestrictions::SetIOAllowed(true);
     base::FileEnumerator it(crash_dumps_dir_, /* recursive */ false,
                             base::FileEnumerator::FILES);

headless/lib/headless_content_main_delegate.cc

@@ -33,10 +33,6 @@
 #include "headless/embedded_resource_pak.h"
 #endif
 
-#if defined(OS_MACOSX)
-#include "components/crash/content/app/crashpad.h"
-#endif
-
 namespace headless {
 namespace {
 // Keep in sync with content/common/content_constants_internal.h.
@@ -163,17 +159,16 @@ void HeadlessContentMainDelegate::InitCrashReporter(
   g_headless_crash_client.Pointer()->set_crash_dumps_dir(
       browser_->options()->crash_dumps_dir);
 
-#if defined(HEADLESS_USE_BREAKPAD)
+#if !defined(OS_MACOSX)
   if (!browser_->options()->enable_crash_reporter) {
     DCHECK(!breakpad::IsCrashReporterEnabled());
     return;
   }
+#if defined(HEADLESS_USE_BREAKPAD)
   if (process_type != switches::kZygoteProcess)
     breakpad::InitCrashReporter(process_type);
-#elif defined(OS_MACOSX)
-  const bool browser_process = process_type.empty();
-  crash_reporter::InitializeCrashpad(browser_process, process_type);
 #endif  // defined(HEADLESS_USE_BREAKPAD)
+#endif  // !defined(OS_MACOSX)
 }
 
 void HeadlessContentMainDelegate::PreSandboxStartup() {
@@ -186,8 +181,10 @@ void HeadlessContentMainDelegate::PreSandboxStartup() {
 #else
   if (command_line.HasSwitch(switches::kEnableLogging))
     InitLogging(command_line);
-#endif  // defined(OS_WIN)
+#endif
+#if !defined(OS_MACOSX)
   InitCrashReporter(command_line);
+#endif
   InitializeResourceBundle();
 }