Fix array pretty formatter

Currently, printing with array pretty formatting makes the output actually
less readable than without:

(gdb) p -array on -- {{1,2,3},{4,5,6}}
$1 =   {    {1,
    2,
    3},
      {4,
    5,
    6}}
(gdb) p -array on -array-indexes on -- {{1,2,3},{4,5,6}}
$2 =   {[0] =     {[0] = 1,
    [1] = 2,
    [2] = 3},
  [1] =     {[0] = 4,
    [1] = 5,
    [2] = 6}}

These changes now also put the first element and the array end bracket on a new
line, similar to the structure pretty formatter:

(gdb) p -array on -- {{1,2,3},{4,5,6}}
$1 = {
  {
    1,
    2,
    3
  },
  {
    4,
    5,
    6
  }
}
(gdb) p -array on -array-indexes on -- {{1,2,3},{4,5,6}}
$2 = {
  [0] = {
    [0] = 1,
    [1] = 2,
    [2] = 3
  },
  [1] = {
    [0] = 4,
    [1] = 5,
    [2] = 6
  }
}

gdb/ChangeLog:

2020-04-29  Hannes Domani  <ssbssa@yahoo.de>

	PR gdb/17320
	* ada-valprint.c (val_print_packed_array_elements): Move array
	end bracket to new line.
	(ada_val_print_string): Remove extra spaces before first array
	element.
	* c-valprint.c (c_value_print_array): Likewise.
	* m2-valprint.c (m2_print_array_contents): Likewise.
	(m2_value_print_inner): Likewise.
	* p-valprint.c (pascal_value_print_inner): Likewise.
	* valprint.c (generic_val_print_array): Likewise.
	(value_print_array_elements): Move first array element and array
	end bracket to new line.

gdb/testsuite/ChangeLog:

2020-04-29  Hannes Domani  <ssbssa@yahoo.de>

	PR gdb/17320
	* gdb.base/pretty-array.c: New test.
	* gdb.base/pretty-array.exp: New file.

1 files changed, 24 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.base/pretty-array.c b/gdb/testsuite/gdb.base/pretty-array.c
new file mode 100644
index 0000000..2adebcc
--- /dev/null
+++ b/gdb/testsuite/gdb.base/pretty-array.c
@@ -0,0 +1,24 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2020 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+int nums[2][3] = {{11, 12, 13}, {21, 22, 23}};
+
+int
+main ()
+{
+  return 0;
+}