[Sampling profiler] Remove unused constructor

There's no need to make a distinction between profiling the current
thread and other threads, and all profiling of the current thread is
already using the other constructor.

Bug: 909957
Change-Id: I5fd82ccbedb52100f7f71809704c8e45f13b8cd3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1513769
Commit-Queue: Charlie Andrews <charliea@chromium.org>
Auto-Submit: Mike Wittman <wittman@chromium.org>
Reviewed-by: Charlie Andrews <charliea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#639554}

base/profiler/stack_sampling_profiler.cc

@@ -625,15 +625,6 @@ void StackSamplingProfiler::TestPeer::PerformSamplingThreadIdleShutdown(
 
 void StackSamplingProfiler::ProfileBuilder::RecordMetadata() {}
 
-StackSamplingProfiler::StackSamplingProfiler(
-    const SamplingParams& params,
-    std::unique_ptr<ProfileBuilder> profile_builder,
-    NativeStackSamplerTestDelegate* test_delegate)
-    : StackSamplingProfiler(PlatformThread::CurrentId(),
-                            params,
-                            std::move(profile_builder),
-                            test_delegate) {}
-
 StackSamplingProfiler::StackSamplingProfiler(
     PlatformThreadId thread_id,
     const SamplingParams& params,

base/profiler/stack_sampling_profiler.h

@@ -124,19 +124,11 @@ class BASE_EXPORT StackSamplingProfiler {
     DISALLOW_COPY_AND_ASSIGN(ProfileBuilder);
   };
 
-  // Creates a profiler for the CURRENT thread. An optional |test_delegate| can
-  // be supplied by tests. The caller must ensure that this object gets
-  // destroyed before the current thread exits.
-  StackSamplingProfiler(
-      const SamplingParams& params,
-      std::unique_ptr<ProfileBuilder> profile_builder,
-      NativeStackSamplerTestDelegate* test_delegate = nullptr);
-
-  // Creates a profiler for ANOTHER thread. An optional |test_delegate| can be
-  // supplied by tests.
+  // Creates a profiler for the specified thread. An optional |test_delegate|
+  // can be supplied by tests.
   //
-  // IMPORTANT: The caller must ensure that the thread being sampled does not
-  // exit before this object gets destructed or Bad Things(tm) may occur.
+  // The caller must ensure that this object gets destroyed before the thread
+  // exits.
   StackSamplingProfiler(
       PlatformThreadId thread_id,
       const SamplingParams& params,