Remove unnecassary parameter "sampleRate" for loadAudioResource().

Parameter "sampleRate" is not required for loadAudioResource().
There is FIXME in AudioBus.cpp in blink
FIXME: the sampleRate parameter is ignored. It should be removed from the API.

It will be consist of 3 steps. 
1. Removing "sampleRate" in chrome which is called by blink. (included deprecated method) 
https://codereview.chromium.org/195043002/ 

2. Removing "sampleRate" in blink. 
https://codereview.chromium.org/194753005/ 

3. Removing deprecated method from #1 

BUG=351284

Review URL: https://codereview.chromium.org/194753005

git-svn-id: svn://svn.chromium.org/blink/trunk@169188 bbb929c8-8fbe-4397-9dbb-9b2b20218538

Source/platform/audio/AudioBus.cpp

@@ -635,10 +635,10 @@ void AudioBus::clearSilentFlag()
         m_channels[i]->clearSilentFlag();
 }
 
-PassRefPtr<AudioBus> decodeAudioFileData(const char* data, size_t size, double sampleRate)
+PassRefPtr<AudioBus> decodeAudioFileData(const char* data, size_t size)
 {
     blink::WebAudioBus webAudioBus;
-    if (blink::Platform::current()->loadAudioResource(&webAudioBus, data, size, sampleRate))
+    if (blink::Platform::current()->loadAudioResource(&webAudioBus, data, size))
         return webAudioBus.release();
     return nullptr;
 }
@@ -649,8 +649,7 @@ PassRefPtr<AudioBus> AudioBus::loadPlatformResource(const char* name, float samp
     if (resource.isEmpty())
         return nullptr;
 
-    // FIXME: the sampleRate parameter is ignored. It should be removed from the API.
-    RefPtr<AudioBus> audioBus = decodeAudioFileData(resource.data(), resource.size(), sampleRate);
+    RefPtr<AudioBus> audioBus = decodeAudioFileData(resource.data(), resource.size());
 
     if (!audioBus.get())
         return nullptr;
@@ -664,8 +663,7 @@ PassRefPtr<AudioBus> AudioBus::loadPlatformResource(const char* name, float samp
 
 PassRefPtr<AudioBus> createBusFromInMemoryAudioFile(const void* data, size_t dataSize, bool mixToMono, float sampleRate)
 {
-    // FIXME: the sampleRate parameter is ignored. It should be removed from the API.
-    RefPtr<AudioBus> audioBus = decodeAudioFileData(static_cast<const char*>(data), dataSize, sampleRate);
+    RefPtr<AudioBus> audioBus = decodeAudioFileData(static_cast<const char*>(data), dataSize);
     if (!audioBus.get())
         return nullptr;
 

public/platform/Platform.h

@@ -393,8 +393,7 @@ class Platform {
     // Decodes the in-memory audio file data and returns the linear PCM audio data in the destinationBus.
     // A sample-rate conversion to sampleRate will occur if the file data is at a different sample-rate.
     // Returns true on success.
-    virtual bool loadAudioResource(WebAudioBus* destinationBus, const char* audioFileData, size_t dataSize, double sampleRate) { return false; }
-
+    virtual bool loadAudioResource(WebAudioBus* destinationBus, const char* audioFileData, size_t dataSize) { return false; }
 
     // Screen -------------------------------------------------------------