Roll third_party/tint/ bc80805c4..5e7ef27ca (9 commits)

https://dawn.googlesource.com/tint/+log/bc80805c4b04..5e7ef27ca7b1

$ git log bc80805c4..5e7ef27ca --date=short --no-merges --format='%ad %ae %s'
2020-08-12 sarahmashay [ast] Adds get last statement to ast::Function
2020-08-12 sarahmashay [validation] Validates functions return statement
2020-08-12 dsinclair Minor updates to fix compilation.
2020-08-12 dsinclair Change output of string based data from sample app.
2020-08-12 idanr Find un-named entry points, change set number
2020-08-12 idanr Add instance step mode to vertex pulling transform
2020-08-12 idanr Add vertex pulling transform
2020-08-11 sarahmashay [validation] Validates declaration name uniqueness
2020-08-11 dsinclair Disable failing tests

Created with:
  roll-dep third_party/tint

Change-Id: I95394bd42e2a02bad36896188c7a1def2d140e78
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/26740
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>

DEPS

@@ -90,7 +90,7 @@ deps = {
 
   # WGSL support
   'third_party/tint': {
-    'url': '{dawn_git}/tint@bc80805c4b04d0e8cd9dad12bef32927363b9787',
+    'url': '{dawn_git}/tint@5e7ef27ca7b1ddedd9a9553bc873e4034cd0c735',
     'condition': 'dawn_standalone',
   },