Added video capture capabilities retrieval and caching to VideoCaptureManager.

                                                                                                                                                                                                                                                                                
The local cache of video capture names and capabilities is created in a
codepath starting in EnumerateDevices. The cache is update during 
StartCaptureForClient() and StopCaptureForClient(). 
                                                                                                                                                                                                                                                                                
Also added unittests (http://goo.gl/QQbpXW).                                                                                                                                                                                                                                                           
                                                                                                                                                                                                                                                                                
BUG=309554

Review URL: https://codereview.chromium.org/29423003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@235223 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 38 insertions, 28 deletions

diff --git a/media/video/capture/fake_video_capture_device.cc b/media/video/capture/fake_video_capture_device.cc
index c36670c..90778a2 100644
--- a/media/video/capture/fake_video_capture_device.cc
+++ b/media/video/capture/fake_video_capture_device.cc
@@ -19,15 +19,23 @@ namespace media {
 static const int kFakeCaptureTimeoutMs = 50;
 static const int kFakeCaptureBeepCycle = 20;  // Visual beep every 1s.
 static const int kFakeCaptureCapabilityChangePeriod = 30;
-enum { kNumberOfFakeDevices = 2 };
 
+int FakeVideoCaptureDevice::number_of_fake_devices_ = 2;
 bool FakeVideoCaptureDevice::fail_next_create_ = false;
 
+void FakeVideoCaptureDevice::SetNumberOfFakeDevices(int num) {
+  number_of_fake_devices_ = num;
+}
+
+int FakeVideoCaptureDevice::NumberOfFakeDevices(void) {
+  return number_of_fake_devices_;
+}
+
 void FakeVideoCaptureDevice::GetDeviceNames(Names* const device_names) {
   // Empty the name list.
   device_names->erase(device_names->begin(), device_names->end());
 
-  for (int n = 0; n < kNumberOfFakeDevices; n++) {
+  for (int n = 0; n < number_of_fake_devices_; n++) {
     Name name(base::StringPrintf("fake_device_%d", n),
               base::StringPrintf("/dev/video%d", n));
     device_names->push_back(name);
@@ -37,12 +45,19 @@ void FakeVideoCaptureDevice::GetDeviceNames(Names* const device_names) {
 void FakeVideoCaptureDevice::GetDeviceSupportedFormats(
     const Name& device,
     VideoCaptureCapabilities* formats) {
-  VideoCaptureCapability capture_format;
-  capture_format.color = media::PIXEL_FORMAT_I420;
-  capture_format.width = 640;
-  capture_format.height = 480;
-  capture_format.frame_rate = 1000 / kFakeCaptureTimeoutMs;
-  formats->push_back(capture_format);
+  formats->clear();
+  VideoCaptureCapability capture_format_640x480;
+  capture_format_640x480.color = media::PIXEL_FORMAT_I420;
+  capture_format_640x480.width = 640;
+  capture_format_640x480.height = 480;
+  capture_format_640x480.frame_rate = 1000 / kFakeCaptureTimeoutMs;
+  formats->push_back(capture_format_640x480);
+  VideoCaptureCapability capture_format_320x240;
+  capture_format_320x240.color = media::PIXEL_FORMAT_I420;
+  capture_format_320x240.width = 320;
+  capture_format_320x240.height = 240;
+  capture_format_320x240.frame_rate = 1000 / kFakeCaptureTimeoutMs;
+  formats->push_back(capture_format_320x240);
 }
 
 VideoCaptureDevice* FakeVideoCaptureDevice::Create(const Name& device_name) {
@@ -50,7 +65,7 @@ VideoCaptureDevice* FakeVideoCaptureDevice::Create(const Name& device_name) {
     fail_next_create_ = false;
     return NULL;
   }
-  for (int n = 0; n < kNumberOfFakeDevices; ++n) {
+  for (int n = 0; n < number_of_fake_devices_; ++n) {
     std::string possible_id = base::StringPrintf("/dev/video%d", n);
     if (device_name.id().compare(possible_id) == 0) {
       return new FakeVideoCaptureDevice();
diff --git a/media/video/capture/fake_video_capture_device.h b/media/video/capture/fake_video_capture_device.h
index 174ba06a..c69fbdf 100644
--- a/media/video/capture/fake_video_capture_device.h
+++ b/media/video/capture/fake_video_capture_device.h
@@ -23,6 +23,8 @@ class MEDIA_EXPORT FakeVideoCaptureDevice : public VideoCaptureDevice {
   // Used for testing. This will make sure the next call to Create will
   // return NULL;
   static void SetFailNextCreate();
+  static void SetNumberOfFakeDevices(int num);
+  static int NumberOfFakeDevices();
 
   static void GetDeviceNames(Names* device_names);
   static void GetDeviceSupportedFormats(const Name& device,
@@ -63,6 +65,7 @@ class MEDIA_EXPORT FakeVideoCaptureDevice : public VideoCaptureDevice {
   std::vector<VideoCaptureCapability> capabilities_roster_;
   int capabilities_roster_index_;
 
+  static int number_of_fake_devices_;
   static bool fail_next_create_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeVideoCaptureDevice);
diff --git a/media/video/capture/mac/video_capture_device_mac.mm b/media/video/capture/mac/video_capture_device_mac.mm
index b353b12..60b193e 100644
--- a/media/video/capture/mac/video_capture_device_mac.mm
+++ b/media/video/capture/mac/video_capture_device_mac.mm
@@ -208,10 +208,17 @@ bool VideoCaptureDeviceMac::Init() {
   DCHECK_EQ(loop_proxy_, base::MessageLoopProxy::current());
   DCHECK_EQ(state_, kNotInitialized);
 
+  // TODO(mcasas): The following check might not be necessary; if the device has
+  // disappeared after enumeration and before coming here, opening would just
+  // fail but not necessarily produce a crash.
   Names device_names;
   GetDeviceNames(&device_names);
-  Name* found = device_names.FindById(device_name_.id());
-  if (!found)
+  Names::iterator it = device_names.begin();
+  for (; it != device_names.end(); ++it) {
+    if (it->id() == device_name_.id())
+      break;
+  }
+  if (it == device_names.end())
     return false;
 
   capture_device_ =
diff --git a/media/video/capture/video_capture_device.cc b/media/video/capture/video_capture_device.cc
index cd1f535..c370d09 100644
--- a/media/video/capture/video_capture_device.cc
+++ b/media/video/capture/video_capture_device.cc
@@ -17,15 +17,6 @@ const std::string VideoCaptureDevice::Name::GetNameAndModel() const {
   return device_name_ + suffix;
 }
 
-VideoCaptureDevice::Name*
-VideoCaptureDevice::Names::FindById(const std::string& id) {
-  for (iterator it = begin(); it != end(); ++it) {
-    if (it->id() == id)
-      return &(*it);
-  }
-  return NULL;
-}
-
 VideoCaptureDevice::~VideoCaptureDevice() {}
 
 }  // namespace media
diff --git a/media/video/capture/video_capture_device.h b/media/video/capture/video_capture_device.h
index 824cdb4..38600c5 100644
--- a/media/video/capture/video_capture_device.h
+++ b/media/video/capture/video_capture_device.h
@@ -18,6 +18,7 @@
 #include "base/logging.h"
 #include "base/time/time.h"
 #include "media/base/media_export.h"
+#include "media/base/video_frame.h"
 #include "media/video/capture/video_capture_types.h"
 
 namespace media {
@@ -109,14 +110,7 @@ class MEDIA_EXPORT VideoCaptureDevice {
   };
 
   // Manages a list of Name entries.
-  class MEDIA_EXPORT Names
-      : public NON_EXPORTED_BASE(std::list<Name>) {
-   public:
-    // Returns NULL if no entry was found by that ID.
-    Name* FindById(const std::string& id);
-
-    // Allow generated copy constructor and assignment.
-  };
+  typedef std::list<Name> Names;
 
   class MEDIA_EXPORT Client {
    public: