Importing rustc-1.49.0

Bug: 176888219
Change-Id: Ib0805d37e7b485cd420bbff8a8b000cf87e7ede0
diff --git a/library/core/src/iter/range.rs b/library/core/src/iter/range.rs
index 9f34aee..cd8ab11 100644
--- a/library/core/src/iter/range.rs
+++ b/library/core/src/iter/range.rs
@@ -713,7 +713,7 @@
         R: Try<Ok = B>,
     {
         if self.is_empty() {
-            return Try::from_ok(init);
+            return try { init };
         }
 
         let mut accum = init;
@@ -731,7 +731,7 @@
             accum = f(accum, self.start.clone())?;
         }
 
-        Try::from_ok(accum)
+        try { accum }
     }
 
     #[inline]
@@ -818,7 +818,7 @@
         R: Try<Ok = B>,
     {
         if self.is_empty() {
-            return Try::from_ok(init);
+            return try { init };
         }
 
         let mut accum = init;
@@ -836,7 +836,7 @@
             accum = f(accum, self.start.clone())?;
         }
 
-        Try::from_ok(accum)
+        try { accum }
     }
 
     #[inline]