Remove the ASTContext parameter from the attribute-related methods of Decl.
The implementations of these methods can Use Decl::getASTContext() to get the ASTContext.

This commit touches a lot of files since call sites for these methods are everywhere.
I used pre-tokenized "carbon.h" and "cocoa.h" headers to do some timings, and there was no real time difference between before the commit and after it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@74501 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/PCHWriterDecl.cpp b/lib/Frontend/PCHWriterDecl.cpp
index 44da4d7..97a3a78 100644
--- a/lib/Frontend/PCHWriterDecl.cpp
+++ b/lib/Frontend/PCHWriterDecl.cpp
@@ -520,7 +520,7 @@
     
     // If the declaration had any attributes, write them now.
     if (D->hasAttrs())
-      WriteAttributeRecord(D->getAttrs(Context));
+      WriteAttributeRecord(D->getAttrs());
 
     // Flush any expressions that were written as part of this declaration.
     FlushStmts();