Add GLES2Implemention::FreeUnusedSharedMemory

gpu/command_buffer/client/mapped_memory.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <algorithm>
 #include <functional>
 
 #include "../client/mapped_memory.h"
 #include "../client/cmd_buffer_helper.h"
 
@@ skipping 70 matching lines @@
   for (size_t ii = 0; ii < chunks_.size(); ++ii) {
     MemoryChunk* chunk = chunks_[ii];
     if (chunk->IsInChunk(pointer)) {
       chunk->FreePendingToken(pointer, token);
       return;
     }
   }
   GPU_NOTREACHED();
 }
 
+void MappedMemoryManager::FreeUnused() {
+  CommandBuffer* cmd_buf = helper_->command_buffer();
+  MemoryChunkVector::iterator iter = chunks_.begin();
+  while (iter != chunks_.end()) {
+    MemoryChunk* chunk = *iter;
+    chunk->FreeUnused();
+    if (!chunk->InUse()) {
+      cmd_buf->DestroyTransferBuffer(chunk->shm_id());
+      iter = chunks_.erase(iter);
+    } else {
+      ++iter;
+    }
+  }
+}
+
 }  // namespace gpu