[modules] Simplify -cc1 interface for enabling implicit module maps.

We used to have a flag to enable module maps, and two more flags to enable
implicit module maps. This is all redundant; we don't need any flag for
enabling module maps in the abstract, and we don't usually have -fno- flags for
-cc1. We now have just a single flag, -fimplicit-module-maps, that enables
implicitly searching the file system for module map files and loading them.

The driver interface is unchanged for now. We should probably rename
-fmodule-maps to -fimplicit-module-maps at some point.

llvm-svn: 239789
diff --git a/clang/test/Modules/build-fail-notes.m b/clang/test/Modules/build-fail-notes.m
index e273411..47bdbc7 100644
--- a/clang/test/Modules/build-fail-notes.m
+++ b/clang/test/Modules/build-fail-notes.m
@@ -1,5 +1,5 @@
 // RUN: rm -rf %t
-// RUN: not %clang_cc1 -fmodules-cache-path=%t -fmodules -F %S/Inputs -DgetModuleVersion="epic fail" %s 2>&1 | FileCheck %s
+// RUN: not %clang_cc1 -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -F %S/Inputs -DgetModuleVersion="epic fail" %s 2>&1 | FileCheck %s
 
 @import DependsOnModule;
 
@@ -11,14 +11,14 @@
 // CHECK: fatal error: could not build module 'DependsOnModule'
 // CHECK-NOT: error:
 
-// RUN: not %clang_cc1 -fmodules-cache-path=%t -fmodules -F %S/Inputs %s -fdiagnostics-show-note-include-stack 2>&1 | FileCheck -check-prefix=CHECK-REDEF %s
+// RUN: not %clang_cc1 -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -F %S/Inputs %s -fdiagnostics-show-note-include-stack 2>&1 | FileCheck -check-prefix=CHECK-REDEF %s
 extern int Module;
 
 // CHECK-REDEF: In module 'DependsOnModule' imported from
 // CHECK-REDEF: In module 'Module' imported from
 // CHECK-REDEF: Module.h:15:12: note: previous definition is here
 
-// RUN: not %clang_cc1 -Wincomplete-umbrella -fmodules-cache-path=%t -fmodules -F %S/Inputs -DgetModuleVersion="epic fail" -serialize-diagnostic-file %t/tmp.diag %s 2>&1
+// RUN: not %clang_cc1 -Wincomplete-umbrella -fmodules-cache-path=%t -fmodules -fimplicit-module-maps -F %S/Inputs -DgetModuleVersion="epic fail" -serialize-diagnostic-file %t/tmp.diag %s 2>&1
 // RUN: c-index-test -read-diagnostics %t/tmp.diag 2>&1 | FileCheck -check-prefix=CHECK-SDIAG %s
 
 // CHECK-SDIAG: Module.h:9:13: error: expected ';' after top level declarator