Support AudioContextOptions latencyHint as double.

media/base/audio_latency.cc

Index: media/base/audio_latency.cc
diff --git a/media/base/audio_latency.cc b/media/base/audio_latency.cc
index 5d37edf415213ff72aeb6e9753927abf1dfb8894..61b3724efa48cc36fc8ff7c3a545c95d7ba5bb56 100644
--- a/media/base/audio_latency.cc
+++ b/media/base/audio_latency.cc
@@ -9,6 +9,7 @@
 #include <algorithm>
 
 #include "base/logging.h"
+#include "base/time/time.h"
 #include "build/build_config.h"
 
 namespace media {
@@ -126,4 +127,19 @@ int AudioLatency::GetInteractiveBufferSize(int hardware_buffer_size) {
   return hardware_buffer_size;
 }
 
+int AudioLatency::GetExactBufferSize(base::TimeDelta duration,
+                                     int sample_rate,
+                                     int hardware_buffer_size) {
+  const double requested_buffer_size = duration.InSecondsF() * sample_rate;
+
+  DCHECK_NE(0, hardware_buffer_size);
+
+  // Round the requested size to the nearest multiple of the hardware size
+  const int buffer_size =
+      std::round(std::max(requested_buffer_size, 1.0) / hardware_buffer_size) *
+      hardware_buffer_size;
+
+  return std::max(buffer_size, hardware_buffer_size);
+}
+
 }  // namespace media