Remove unnecessary -weak_framework CoreBluetooth.

Chromium now requires 10.10+, so weak-linking a framework that is
always available is not necessary.

Bug: 840435
Change-Id: I88bed9c971450441b79b961e3d08443acadc9644
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2062928Reviewed-by: Colin Blundell <blundell@chromium.org>
Commit-Queue: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#742630}

device/BUILD.gn

@@ -246,20 +246,10 @@ test("device_unittests") {
     deps += [ "//third_party/ocmock" ]
     ldflags = [ "-ObjC" ]
     libs = [
+      "CoreBluetooth.framework",
       "IOBluetooth.framework",
       "IOKit.framework",
     ]
-
-    # In the OSX 10.10 SDK, CoreBluetooth became a top level framework.
-    # Previously, it was nested in IOBluetooth. In order for Chrome to run on
-    # OSes older than OSX 10.10, the top level CoreBluetooth framework must be
-    # weakly linked.
-    if (mac_sdk_version == "10.10") {
-      ldflags += [
-        "-weak_framework",
-        "CoreBluetooth",
-      ]
-    }
   }
 
   if (is_win) {