Refactor AudioParameters member setting.

Permit AudioParameters members to be set individually. Allows us to:
- Cut back to the one non-default constructor which is frequently used.
- Remove a bunch of boilerplate in the common case of updating one
member.
- Make adding future optional members (e.g. mic_positions)
transparent to most callers.

Maintain the Reset method but remove the channels parameter to have it
mirror the constructor.

Make it clear that channels_ is only required to be set explicitly with
CHANNEL_LAYOUT_DISCRETE.

BUG=497001

Review URL: https://codereview.chromium.org/1304973005

Cr-Commit-Position: refs/heads/master@{#347781}

1 files changed, 3 insertions, 12 deletions

diff --git a/media/audio/audio_parameters_unittest.cc b/media/audio/audio_parameters_unittest.cc
index 92677eb..2cf541d 100644
--- a/media/audio/audio_parameters_unittest.cc
+++ b/media/audio/audio_parameters_unittest.cc
@@ -205,20 +205,11 @@ TEST(AudioParameters, Compare) {
 
 TEST(AudioParameters, Constructor_ValidChannelCounts) {
   int expected_channels = 8;
-  ChannelLayout expected_layout = CHANNEL_LAYOUT_5_1;
+  ChannelLayout expected_layout = CHANNEL_LAYOUT_DISCRETE;
 
   AudioParameters params(AudioParameters::AUDIO_PCM_LOW_LATENCY,
-                         expected_layout, expected_channels, 44100, 16, 880,
-                         AudioParameters::NO_EFFECTS);
-
-  EXPECT_EQ(expected_channels, params.channels());
-  EXPECT_EQ(expected_layout, params.channel_layout());
-  EXPECT_FALSE(params.IsValid());
-
-  expected_layout = CHANNEL_LAYOUT_DISCRETE;
-  params.Reset(AudioParameters::AUDIO_PCM_LOW_LATENCY, expected_layout,
-               expected_channels, 44100, 16, 880);
-
+                         expected_layout, 44100, 16, 880);
+  params.set_channels_for_discrete(expected_channels);
   EXPECT_EQ(expected_channels, params.channels());
   EXPECT_EQ(expected_layout, params.channel_layout());
   EXPECT_TRUE(params.IsValid());