Revert "Use uint64_t for branch weights instead of uint32_t"

This reverts commit e5766f25c62c185632e3a75bf45b313eadab774b.
Makes clang assert when building Chromium, see https://crbug.com/1142813
for a repro.
diff --git a/clang/test/Profile/cxx-lambda.cpp b/clang/test/Profile/cxx-lambda.cpp
index 3486e10..08d78da 100644
--- a/clang/test/Profile/cxx-lambda.cpp
+++ b/clang/test/Profile/cxx-lambda.cpp
@@ -45,12 +45,12 @@
   if (i) {}
 }
 
-// PGOUSE-DAG: ![[LW1]] = !{!"branch_weights", i64 2, i64 1}
-// PGOUSE-DAG: ![[LW2]] = !{!"branch_weights", i64 11, i64 2}
-// PGOUSE-DAG: ![[LW3]] = !{!"branch_weights", i64 2, i64 1}
+// PGOUSE-DAG: ![[LW1]] = !{!"branch_weights", i32 2, i32 1}
+// PGOUSE-DAG: ![[LW2]] = !{!"branch_weights", i32 11, i32 2}
+// PGOUSE-DAG: ![[LW3]] = !{!"branch_weights", i32 2, i32 1}
 
-// LMBUSE-DAG: ![[LF1]] = !{!"branch_weights", i64 10, i64 2}
-// LMBUSE-DAG: ![[LF2]] = !{!"branch_weights", i64 10, i64 2}
+// LMBUSE-DAG: ![[LF1]] = !{!"branch_weights", i32 10, i32 2}
+// LMBUSE-DAG: ![[LF2]] = !{!"branch_weights", i32 10, i32 2}
 
 int main(int argc, const char *argv[]) {
   lambdas();