FBTF: Fix more ctor/dtors found by clang plugin.

gpu/command_buffer/service/common_decoder.cc

Index: gpu/command_buffer/service/common_decoder.cc
diff --git a/gpu/command_buffer/service/common_decoder.cc b/gpu/command_buffer/service/common_decoder.cc
index c28c448be3519985dc81b223c3361bf8e19d1d7c..ce45422eda9e66090e0f8fa131eef2ca2934bbbe 100644
--- a/gpu/command_buffer/service/common_decoder.cc
+++ b/gpu/command_buffer/service/common_decoder.cc
@@ -7,6 +7,10 @@
 
 namespace gpu {
 
+CommonDecoder::Bucket::Bucket() : size_(0) {}
+
+CommonDecoder::Bucket::~Bucket() {}
+
 void* CommonDecoder::Bucket::GetData(size_t offset, size_t size) const {
   if (OffsetSizeValid(offset, size)) {
     return data_.get() + offset;
@@ -47,6 +51,10 @@ bool CommonDecoder::Bucket::GetAsString(std::string* str) {
   return true;
 }
 
+CommonDecoder::CommonDecoder() : engine_(NULL) {}
+
+CommonDecoder::~CommonDecoder() {}
+
 void* CommonDecoder::GetAddressAndCheckSize(unsigned int shm_id,
                                             unsigned int offset,
                                             unsigned int size) {