Add prefix to empty param tests.

googletest will no longer support empty prefix
for parameterized INSTANTIATE_TEST_SUITE_P.
Adding "All" prefix to existing empty prefix test suites.

This CL was uploaded by git cl split.

R=henrika@chromium.org

Bug: 1023677
Change-Id: I0948465a50da42cf6b23eeb4de7a8c6a3c41e3ea
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1957556
Auto-Submit: Ilia Samsonov <isamsonov@google.com>
Reviewed-by: Henrik Andreasson <henrika@chromium.org>
Commit-Queue: Ilia Samsonov <isamsonov@google.com>
Cr-Commit-Position: refs/heads/master@{#722943}

media/base/audio_latency_unittest.cc

@@ -165,7 +165,7 @@ TEST_P(AudioLatencyTest, ExactBufferSizes) {
 }
 
 INSTANTIATE_TEST_SUITE_P(
-    /* no prefix */,
+    All,
     AudioLatencyTest,
 #if defined(OS_WIN)
     // Windows 10 with supported driver will have valid min and max buffer sizes