[iOS] Fix OpenInController for multiple files

The |_documentController| wasn't reset between two files, leading to
an issue where it wasn't pointing to the correct file.

Fixed: 1062392
Change-Id: I5c4214c793c0e4e10f2c16af189c899683ba95b0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2111092
Commit-Queue: Mark Cogan <marq@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Auto-Submit: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#752002}

ios/chrome/browser/ui/open_in/open_in_controller.mm

@@ -438,12 +438,8 @@ class OpenInControllerBridge
   if (!_webState)
     return;
 
-  if (!_documentController) {
-    // If this is called from a unit test, |documentController_| was set
-    // already.
-    _documentController =
-        [UIDocumentInteractionController interactionControllerWithURL:fileURL];
-  }
+  _documentController =
+      [UIDocumentInteractionController interactionControllerWithURL:fileURL];
 
   // TODO(cgrigoruta): The UTI is hardcoded for now, change this when we add
   // support for other file types as well.
@@ -699,11 +695,6 @@ class OpenInControllerBridge
 
 #pragma mark - TestingAditions
 
-- (void)setDocumentInteractionController:
-    (UIDocumentInteractionController*)controller {
-  _documentController = controller;
-}
-
 - (NSString*)suggestedFilename {
   return _suggestedFilename;
 }

ios/chrome/browser/ui/open_in/open_in_controller_testing.h

@@ -8,8 +8,6 @@
 @interface OpenInController (TestingAditions)
 - (NSString*)suggestedFilename;
 - (void)startDownload;
-- (void)setDocumentInteractionController:
-    (UIDocumentInteractionController*)controller;
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_OPEN_IN_OPEN_IN_CONTROLLER_TESTING_H_

ios/chrome/browser/ui/open_in/open_in_controller_unittest.mm

@@ -86,7 +86,9 @@ TEST_F(OpenInControllerTest, TestDisplayOpenInMenu) {
   histogram_tester_.ExpectTotalCount(kOpenInDownloadResultHistogram, 0);
   id document_controller =
       [OCMockObject niceMockForClass:[UIDocumentInteractionController class]];
-  [open_in_controller_ setDocumentInteractionController:document_controller];
+  id classMock = OCMClassMock([UIDocumentInteractionController class]);
+  OCMStub([classMock interactionControllerWithURL:[OCMArg any]])
+      .andReturn(document_controller);
   [open_in_controller_ startDownload];
   [[[document_controller expect] andReturnValue:@YES]
       presentOpenInMenuFromRect:CGRectZero
@@ -109,9 +111,12 @@ TEST_F(OpenInControllerTest, TestDisplayOpenInMenu) {
 
 TEST_F(OpenInControllerTest, TestCorruptedPDFDownload) {
   histogram_tester_.ExpectTotalCount(kOpenInDownloadResultHistogram, 0);
+
   id document_controller =
       [OCMockObject niceMockForClass:[UIDocumentInteractionController class]];
-  [open_in_controller_ setDocumentInteractionController:document_controller];
+  id classMock = OCMClassMock([UIDocumentInteractionController class]);
+  OCMStub([classMock interactionControllerWithURL:[OCMArg any]])
+      .andReturn(document_controller);
   [open_in_controller_ startDownload];
   [[[document_controller reject] andReturnValue:@YES]
       presentOpenInMenuFromRect:CGRectZero