[Patch] BaseTool: Fixed the issue of empty PcdDB.

[BobCF <bob.c.feng@intel.com>]

If there is no dynamic pcds, there should be DB header
in the Pcd DataBase.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
---
 BaseTools/Source/Python/AutoGen/GenPcdDb.py | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/BaseTools/Source/Python/AutoGen/GenPcdDb.py b/BaseTools/Source/Python/AutoGen/GenPcdDb.py
index e2848e7aaf..e4d7f3b759 100644
--- a/BaseTools/Source/Python/AutoGen/GenPcdDb.py
+++ b/BaseTools/Source/Python/AutoGen/GenPcdDb.py
@@ -978,12 +978,10 @@ def CreatePcdDatabaseCode (Info, AutoGenC, AutoGenH):
     DbFile.write(PcdDbBuffer)
     Changed = SaveFileOnChange(DbFileName, DbFile.getvalue(), True)
 def CreatePcdDataBase(PcdDBData):
     delta = {}
     basedata = {}
-    if not PcdDBData:
-        return ""
     for skuname,skuid in PcdDBData:
         if len(PcdDBData[(skuname,skuid)][1]) != len(PcdDBData[("DEFAULT","0")][1]):
             EdkLogger.ERROR("The size of each sku in one pcd are not same")
     for skuname,skuid in PcdDBData:
         if skuname == "DEFAULT":
@@ -1059,13 +1057,16 @@ def NewCreatePcdDatabasePhaseSpecificAutoGen(Platform,Phase):
             VarCheckTable = CreateVarCheckBin(VarCheckTableData)
             VarCheckTable.dump(dest, Phase)
         AdditionalAutoGenH, AdditionalAutoGenC =  CreateAutoGen(PcdDriverAutoGenData)
     else:
         AdditionalAutoGenH, AdditionalAutoGenC, PcdDbBuffer,VarCheckTab = CreatePcdDatabasePhaseSpecificAutoGen (Platform,{}, Phase)
+        final_data = ()
+        for item in PcdDbBuffer:
+            final_data += unpack("B",item)
+        PcdDBData[("DEFAULT","0")] = (PcdDbBuffer, final_data)
 
-    PcdDbBuffer = CreatePcdDataBase(PcdDBData)
-    return AdditionalAutoGenH, AdditionalAutoGenC, PcdDbBuffer
+    return AdditionalAutoGenH, AdditionalAutoGenC, CreatePcdDataBase(PcdDBData)
 ## Create PCD database in DXE or PEI phase
 #
 #   @param      Platform    The platform object
 #   @retval     tuple       Two TemplateString objects for C code and header file,
 #                           respectively
-- 
2.14.3.windows.1