[trie] Save hash value when node is created from proto

[Liuhaai]

No description provided.

[codecov]

Codecov Report

Merging #3170 (18e5643) into master (12976b9) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #3170   +/-   ##
=======================================
  Coverage   75.06%   75.07%           
=======================================
  Files         220      220           
  Lines       20978    20982    +4     
=======================================
+ Hits        15748    15752    +4     
  Misses       4394     4394           
  Partials      836      836           

Impacted Files	Coverage Δ
db/trie/mptrie/branchnode.go	98.61% <100.00%> (+0.01%)	⬆️
db/trie/mptrie/extensionnode.go	92.98% <100.00%> (+0.06%)	⬆️
db/trie/mptrie/leafnode.go	100.00% <100.00%> (ø)
db/trie/mptrie/merklepatriciatrie.go	91.48% <100.00%> (ø)

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