Rename DecodeCFAndKey to resolve naming conflict in unity test (#4323)

Summary:
Currently unity-test is failing because both trace_replay.cc and trace_analyzer_tool.cc defined `DecodeCFAndKey` under anonymous namespace. It is supposed to be fine except unity test will dump all source files together and now we have a conflict.
Another issue with trace_analyzer_tool.cc is that it is using some utility functions from ldb_cmd which is not included in Makefile for unity_test, I chose to update TESTHARNESS to include LIBOBJECTS. Feel free to comment if there is a less intrusive way to solve this.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4323

Differential Revision: D9599170

Pulled By: miasantreble

fbshipit-source-id: 38765b11f8e7de92b43c63bdcf43ea914abdc029

Makefile

@@ -1002,8 +1002,10 @@ unity.a: unity.o
 	$(AM_V_AR)rm -f $@
 	$(AM_V_at)$(AR) $(ARFLAGS) $@ unity.o
 
+
+TOOLLIBOBJECTS = $(TOOL_LIB_SOURCES:.cc=.o)
 # try compiling db_test with unity
-unity_test: db/db_test.o db/db_test_util.o $(TESTHARNESS) unity.a
+unity_test: db/db_test.o db/db_test_util.o $(TESTHARNESS) $(TOOLLIBOBJECTS) unity.a
 	$(AM_LINK)
 	./unity_test
 

tools/trace_analyzer_tool.cc

@@ -185,7 +185,7 @@ uint64_t MultiplyCheckOverflow(uint64_t op1, uint64_t op2) {
   return (op1 * op2);
 }
 
-void DecodeCFAndKey(std::string& buffer, uint32_t* cf_id, Slice* key) {
+void DecodeCFAndKeyFromString(std::string& buffer, uint32_t* cf_id, Slice* key) {
   Slice buf(buffer);
   GetFixed32(&buf, cf_id);
   GetLengthPrefixedSlice(&buf, key);
@@ -459,7 +459,7 @@ Status TraceAnalyzer::StartProcessing() {
     } else if (trace.type == kTraceGet) {
       uint32_t cf_id = 0;
       Slice key;
-      DecodeCFAndKey(trace.payload, &cf_id, &key);
+      DecodeCFAndKeyFromString(trace.payload, &cf_id, &key);
       total_gets_++;
 
       s = HandleGet(cf_id, key.ToString(), trace.ts, 1);
@@ -471,7 +471,7 @@ Status TraceAnalyzer::StartProcessing() {
                trace.type == kTraceIteratorSeekForPrev) {
       uint32_t cf_id = 0;
       Slice key;
-      DecodeCFAndKey(trace.payload, &cf_id, &key);
+      DecodeCFAndKeyFromString(trace.payload, &cf_id, &key);
       s = HandleIter(cf_id, key.ToString(), trace.ts, trace.type);
       if (!s.ok()) {
         fprintf(stderr, "Cannot process the iterator in the trace\n");