Revert of cc: Implement shared worker contexts.

content/child/child_thread_impl.cc

Index: content/child/child_thread_impl.cc
diff --git a/content/child/child_thread_impl.cc b/content/child/child_thread_impl.cc
index 8c5291d880bcb076aba35fa3d291692f0f92b47b..bfb1f3a21bf3d4fe20fd40242e37debfd6673457 100644
--- a/content/child/child_thread_impl.cc
+++ b/content/child/child_thread_impl.cc
@@ -590,7 +590,7 @@
   shared_buf.reset(new base::SharedMemory);
   if (!shared_buf->CreateAnonymous(buf_size)) {
     NOTREACHED();
-    return nullptr;
+    return NULL;
   }
 #else
   // On POSIX, we need to ask the browser to create the shared memory for us,
@@ -602,14 +602,11 @@
       shared_buf.reset(new base::SharedMemory(shared_mem_handle, false));
     } else {
       NOTREACHED() << "Browser failed to allocate shared memory";
-      return nullptr;
+      return NULL;
     }
-  } else if (ChildProcess::current()->GetShutDownEvent()->IsSignaled()) {
-    // Send is allowed to fail during shutdown. Return null in this case.
-    return nullptr;
   } else {
     NOTREACHED() << "Browser allocation request message failed";
-    return nullptr;
+    return NULL;
   }
 #endif
   return shared_buf;