Implement FPDFAction_GetFilePath().

testing/resources/launch_action.pdf

Index: testing/resources/launch_action.pdf
diff --git a/testing/resources/hello_world.pdf b/testing/resources/launch_action.pdf
similarity index 51%
copy from testing/resources/hello_world.pdf
copy to testing/resources/launch_action.pdf
index bb4f0a88e7aedbbdbe4bdc6b22ff0696bed0282b..99a42923deead8813fdc98d454e88200e1f72d91 100644
--- a/testing/resources/hello_world.pdf
+++ b/testing/resources/launch_action.pdf
@@ -14,39 +14,37 @@ endobj
 3 0 obj <<
   /Type /Page
   /Parent 2 0 R
-  /Resources <<
-    /Font <<
-      /F1 4 0 R
-      /F2 5 0 R
-    >>
-  >>
-  /Contents 6 0 R
+  /Annots [4 0 R]
 >>
 endobj
 4 0 obj <<
-  /Type /Font
-  /Subtype /Type1
-  /BaseFont /Times-Roman
+  /A 5 0 R
+  /FT /Tx
+  /Ff 29360128
+  /T (txtName)
+  /Type /Annot
+  /Subtype /Link
+  /F 4
+  /M (D:20150514070426+05'30')
+  /Rect [1 1 199 199]
+  /BS  <<
+    /W 1
+    /S /S
+  >>
+  /DA (/Helv 0 Tf 0 0 0 rg)
+  /AP <</N 8 0 R>>
+  /V ()
+  /AA 19 0 R
 >>
 endobj
 5 0 obj <<
-  /Type /Font
-  /Subtype /Type1
-  /BaseFont /Helvetica
+  /F 6 0 R
+  /S /Launch
 >>
-endobj
 6 0 obj <<
+  /F (test.pdf)
+  /Type / Filespec
 >>
-stream
-BT
-20 50 Td
-/F1 12 Tf
-(Hello, world!) Tj
-0 50 Td
-/F2 16 Tf
-(Goodbye, world!) Tj
-ET
-endstream
 endobj
 xref
 0 7
@@ -54,13 +52,13 @@ xref
 0000000015 00000 n 
 0000000061 00000 n 
 0000000154 00000 n 
-0000000296 00000 n 
-0000000374 00000 n 
-0000000450 00000 n 
+0000000223 00000 n 
+0000000489 00000 n 
+0000000527 00000 n 
 trailer <<
   /Size 6
   /Root 1 0 R
 >>
 startxref
-571
+583
 %%EOF