Verbosity and increase buffer limit

New MediaSource inline/shared buffer threshold meant we hit max buffers
allowed limit more often -- with verbose diagnostics.
max buffers now aligned with primary consumer NuMediaExtractor (4->8)

Bug: 115848790
Test: poc

media/libmedia/IMediaSource.cpp

@@ -368,13 +368,13 @@ status_t BnMediaSource::onTransact(
                         ALOGV("Use shared memory: %zu", length);
                         transferBuf = buf;
                     } else {
-                        ALOGD("Large buffer %zu without IMemory!", length);
+                        ALOGV("Large buffer %zu without IMemory!", length);
                         ret = mGroup->acquire_buffer(
                                 (MediaBufferBase **)&transferBuf, false /* nonBlocking */, length);
                         if (ret != OK
                                 || transferBuf == nullptr
                                 || transferBuf->mMemory == nullptr) {
-                            ALOGW("Failed to acquire shared memory, size %zu, ret %d",
+                            ALOGV("Failed to acquire shared memory, size %zu, ret %d",
                                     length, ret);
                             if (transferBuf != nullptr) {
                                 transferBuf->release();

media/libmedia/include/media/IMediaSource.h

@@ -124,7 +124,8 @@ public:
         return false;
     }
 
-    static const size_t kBinderMediaBuffers = 4; // buffers managed by BnMediaSource
+    // align buffer count with video request size in NuMediaExtractor::selectTrack()
+    static const size_t kBinderMediaBuffers = 8; // buffers managed by BnMediaSource
     static const size_t kTransferSharedAsSharedThreshold = 4 * 1024;  // if >= shared, else inline
     static const size_t kTransferInlineAsSharedThreshold = 8 * 1024; // if >= shared, else inline
     static const size_t kInlineMaxTransfer = 64 * 1024; // Binder size limited to BINDER_VM_SIZE.