Clang-format: add finer-grained options for putting all arguments on one line

Summary:
Add two new options,
AllowAllArgumentsOnNextLine and
AllowAllConstructorInitializersOnNextLine.  These mirror the existing
AllowAllParametersOfDeclarationOnNextLine and allow me to support an
internal style guide where I work.  I think this would be generally
useful, some have asked for it on stackoverflow:

https://stackoverflow.com/questions/30057534/clang-format-binpackarguments-not-working-as-expected

https://stackoverflow.com/questions/38635106/clang-format-how-to-prevent-all-function-arguments-on-next-line

Reviewers: djasper, krasimir, MyDeveloperDay

Reviewed By: MyDeveloperDay

Subscribers: jkorous, MyDeveloperDay, aol-nnov, lebedev.ri, uohcsemaj, cfe-commits, klimek

Differential Revision: https://reviews.llvm.org/D40988

Patch By: russellmcc  (Russell McClellan)

llvm-svn: 356834
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 5fe118a..2d1adb5 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -335,6 +335,10 @@
     IO.mapOptional("AlignEscapedNewlines", Style.AlignEscapedNewlines);
     IO.mapOptional("AlignOperands", Style.AlignOperands);
     IO.mapOptional("AlignTrailingComments", Style.AlignTrailingComments);
+    IO.mapOptional("AllowAllArgumentsOnNextLine",
+                   Style.AllowAllArgumentsOnNextLine);
+    IO.mapOptional("AllowAllConstructorInitializersOnNextLine",
+                   Style.AllowAllConstructorInitializersOnNextLine);
     IO.mapOptional("AllowAllParametersOfDeclarationOnNextLine",
                    Style.AllowAllParametersOfDeclarationOnNextLine);
     IO.mapOptional("AllowShortBlocksOnASingleLine",
@@ -351,6 +355,7 @@
                    Style.AlwaysBreakAfterDefinitionReturnType);
     IO.mapOptional("AlwaysBreakAfterReturnType",
                    Style.AlwaysBreakAfterReturnType);
+
     // If AlwaysBreakAfterDefinitionReturnType was specified but
     // AlwaysBreakAfterReturnType was not, initialize the latter from the
     // former for backwards compatibility.
@@ -641,6 +646,8 @@
   LLVMStyle.AlignTrailingComments = true;
   LLVMStyle.AlignConsecutiveAssignments = false;
   LLVMStyle.AlignConsecutiveDeclarations = false;
+  LLVMStyle.AllowAllArgumentsOnNextLine = true;
+  LLVMStyle.AllowAllConstructorInitializersOnNextLine = true;
   LLVMStyle.AllowAllParametersOfDeclarationOnNextLine = true;
   LLVMStyle.AllowShortFunctionsOnASingleLine = FormatStyle::SFS_All;
   LLVMStyle.AllowShortBlocksOnASingleLine = false;