OOP PDF: Change the save toolbar button to match the save menu behavior.

Previously, the save toolbar button for the out-of-process PDF plugin
was a link to the PDF URL. This did not function for file URLs or PDFs
returned in response to a POST. This changes the button to use the
pepper PDF save API and adds a way for a WebContentsDelegate to override
SaveFrame behavior so the MimeHandlerViewGuest can instruct its embedder
to handle the actual save.

BUG=416329
TEST=Run with --out-of-process-pdf.
Open a local PDF and click the save toolbar button. The save as dialog
should appear.
Repeat the same with a PDF returned by a POST request. Saving should
save the opened PDF - not the page returned by a GET to the same URL.

Review URL: https://codereview.chromium.org/706823004

Cr-Commit-Position: refs/heads/master@{#304920}

1 files changed, 4 insertions, 0 deletions

diff --git a/pdf/out_of_process_instance.cc b/pdf/out_of_process_instance.cc
index e195067..4854961 100644
--- a/pdf/out_of_process_instance.cc
+++ b/pdf/out_of_process_instance.cc
@@ -85,6 +85,8 @@ const char kJSGetPasswordCompleteType[] = "getPasswordComplete";
 const char kJSPassword[] = "password";
 // Print (Page -> Plugin)
 const char kJSPrintType[] = "print";
+// Save (Page -> Plugin)
+const char kJSSaveType[] = "save";
 // Go to page (Plugin -> Page)
 const char kJSGoToPageType[] = "goToPage";
 const char kJSPageNumber[] = "page";
@@ -404,6 +406,8 @@ void OutOfProcessInstance::HandleMessage(const pp::Var& message) {
     }
   } else if (type == kJSPrintType) {
     Print();
+  } else if (type == kJSSaveType) {
+    pp::PDF::SaveAs(this);
   } else if (type == kJSRotateClockwiseType) {
     RotateClockwise();
   } else if (type == kJSRotateCounterclockwiseType) {