chore: cherry-pick some inj changes (#17109)

math/CHANGELOG.md

@@ -38,7 +38,8 @@ Ref: https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.j
 
 ## Improvements
 
-* [#16263](https://github.com/cosmos/cosmos-sdk/pull/16263) Improved math/Int.Size by computing the decimal digits count instead of firstly invoking .Marshal() then checking the length
+* [#17109](https://github.com/cosmos/cosmos-sdk/pull/17109) Add `.ToLegacyDec()` method on `math.Int` type for converting to `math.LegacyDec`.
+* [#16263](https://github.com/cosmos/cosmos-sdk/pull/16263) Improved `math/Int.Size` by computing the decimal digits count instead of firstly invoking .Marshal() then checking the length
 
 ### Bug Fixes
 

math/int.go

@@ -154,6 +154,11 @@ func ZeroInt() Int { return Int{big.NewInt(0)} }
 // OneInt returns Int value with one
 func OneInt() Int { return Int{big.NewInt(1)} }
 
+// ToLegacyDec converts Int to LegacyDec
+func (i Int) ToLegacyDec() LegacyDec {
+	return LegacyNewDecFromInt(i)
+}
+
 // Int64 converts Int to int64
 // Panics if the value is out of range
 func (i Int) Int64() int64 {