[lldb/API] Add convenience constructor for SBError (NFC)

This patch adds a new convience constructor to the SBError to initialize
it with a string message to avoid having to create the object and call
the `SetErrorString` method afterwards.

This is very handy to report errors from lldb scripted affordances.

Differential Revision: https://reviews.llvm.org/D148401

Signed-off-by: Med Ismail Bennani <[email protected]>

Author: medismailben

lldb/bindings/interface/SBError.i

@@ -59,6 +59,8 @@ class SBError {
 public:
     SBError ();
 
+    SBError(const char *message);
+
     SBError (const lldb::SBError &rhs);
 
     ~SBError();

lldb/include/lldb/API/SBError.h

@@ -23,6 +23,8 @@ class LLDB_API SBError {
 
   SBError(const lldb::SBError &rhs);
 
+  SBError(const char *message);
+
   SBError(const lldb_private::Status &error);
 
   ~SBError();

lldb/source/API/SBError.cpp

@@ -25,6 +25,12 @@ SBError::SBError(const SBError &rhs) {
   m_opaque_up = clone(rhs.m_opaque_up);
 }
 
+SBError::SBError(const char *message) {
+  LLDB_INSTRUMENT_VA(this, message);
+
+  SetErrorString(message);
+}
+
 SBError::SBError(const lldb_private::Status &status)
     : m_opaque_up(new Status(status)) {
   LLDB_INSTRUMENT_VA(this, status);