Revert "adb: make benchmarks build on the host."

This reverts commit d04b452.

Breaks the darwin build.

Change-Id: If95266c6fc027cf2a706f3c83dce7e50b762b8aa

Android.bp

@@ -213,7 +213,6 @@ cc_test_host {
 cc_benchmark {
     name: "adb_benchmark",
     defaults: ["adb_defaults"],
-    host_supported: true,
 
     srcs: ["transport_benchmark.cpp"],
     target: {
@@ -227,9 +226,6 @@ cc_benchmark {
                 "libadb_host",
             ],
         },
-        darwin: {
-            enabled: false,
-        }
     },
 
     static_libs: [

transport_benchmark.cpp

@@ -183,10 +183,8 @@ ADB_CONNECTION_BENCHMARK(BM_Connection_Echo, ThreadPolicy::SameThread);
 ADB_CONNECTION_BENCHMARK(BM_Connection_Echo, ThreadPolicy::MainThread);
 
 int main(int argc, char** argv) {
-#if defined(__BIONIC__)
     // Set M_DECAY_TIME so that our allocations aren't immediately purged on free.
     mallopt(M_DECAY_TIME, 1);
-#endif
 
     android::base::SetMinimumLogSeverity(android::base::WARNING);
     adb_trace_init(argv);