Modify depot_tools instructions regarding %PATH%

The old depot_tools instructions insisted that depot_tools be the last
entry in the PATH environment variable, for reasons that are unclear and
may only have applied to Linux. Meanwhile, there is a gn issue that can
cause unnecessary building if depot_tools is not near the front of the
path - ahead of other Python installs. This change alters the
instructions for Windows.

This also removes some obsolete instructions regarding building Chrome
on Windows XP - Chrome doesn't even *run* on Windows XP anymore.

BUG=611087

Review-Url: https://codereview.chromium.org/2371333002

man/html/depot_tools_tutorial.html

@@ -898,8 +898,8 @@ extract the hidden &#8220;.git&#8221; folder which is necessary for <em>depot_to
 autoupdate itself. You can use &#8220;Extract all&#8230;&#8221; from the context menu though.</td>
 </tr></table>
 </div>
-<div class="paragraph"><p>Add <em>depot_tools</em> to the <em>end</em> of your PATH. Assuming you unzipped the
-bundle to <code>C:\workspace\depot_tools</code>:</p></div>
+<div class="paragraph"><p>Add <em>depot_tools</em> to the <em>start</em> of your PATH (must be ahead of any installs of
+Python). Assuming you unzipped the bundle to <code>C:\workspace\depot_tools</code>:</p></div>
 <div class="dlist"><dl>
 <dt class="hdlist1">
 With Administrator access: 
@@ -917,7 +917,7 @@ Without Administrator access:
 <p>
   <strong>Control Panel &#8594; User Accounts &#8594; User Accounts &#8594; Change my environment variables</strong>
 </p>
-<div class="paragraph"><p>Add a PATH user variable: <code>%PATH%;C:\workspace\depot_tools</code>.</p></div>
+<div class="paragraph"><p>Add a PATH user variable: <code>C:\workspace\depot_tools;%PATH%</code>.</p></div>
 </dd>
 </dl></div>
 <div class="paragraph"><p>From a <code>cmd.exe</code> shell, run the command <code>gclient</code> (without arguments). On first
@@ -946,10 +946,10 @@ If you see strange errors with the file system on the first run of gclient,
 </li>
 <li>
 <p>
-If you are running Windows XP and see errors like &#8220;The system cannot execute
-  the specified program&#8221;, try installing the
-  <a href="http://code.google.com/p/chromium/issues/detail?id=75886">&#8220;Microsoft
-  Visual C++ 2008 Redistributable Package&#8221;</a>.
+After running gclient open a command prompt and type <code>where python</code> and confirm that
+  the depot_tools python.bat comes ahead of any copies of python.exe. Failing to ensure
+  this can lead to overbuilding when using gn - see
+  <a href="https://bugs.chromium.org/p/chromium/issues/detail?id=611087">crbug.com/611087</a>.
 </p>
 </li>
 </ul></div>
@@ -1573,14 +1573,14 @@ LKGR
 <div class="sectionbody">
 <div class="paragraph"><p>Part of the chromium <a href="depot_tools.html">depot_tools(7)</a> suite. These tools are meant to
 assist with the development of chromium and related projects. Download the tools
-from <a href="https://chromium.googlesource.com/chromium/tools/depot_tools">here</a>.</p></div>
+from <a href="https://chromium.googlesource.com/chromium/tools/depot_tools.git">here</a>.</p></div>
 </div>
 </div>
 </div>
 <div id="footnotes"><hr /></div>
 <div id="footer">
 <div id="footer-text">
-Last updated 2016-07-21 10:09:00 PDT
+Last updated 2016-09-28 15:37:50 PDT
 </div>
 </div>
 </body>

man/man7/depot_tools_tutorial.7

@@ -2,12 +2,12 @@
 .\"     Title: depot_tools_tutorial
 .\"    Author: [FIXME: author] [see http://docbook.sf.net/el/author]
 .\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
-.\"      Date: 07/21/2016
+.\"      Date: 09/28/2016
 .\"    Manual: Chromium depot_tools Manual
-.\"    Source: depot_tools bf2a341
+.\"    Source: depot_tools daffbcf
 .\"  Language: English
 .\"
-.TH "DEPOT_TOOLS_TUTORIAL" "7" "07/21/2016" "depot_tools bf2a341" "Chromium depot_tools Manual"
+.TH "DEPOT_TOOLS_TUTORIAL" "7" "09/28/2016" "depot_tools daffbcf" "Chromium depot_tools Manual"
 .\" -----------------------------------------------------------------
 .\" * Define some portability stuff
 .\" -----------------------------------------------------------------
@@ -1051,5 +1051,5 @@ main Chromium waterfall
 .IP " 7." 4
 here
 .RS 4
-\%https://chromium.googlesource.com/chromium/tools/depot_tools
+\%https://chromium.googlesource.com/chromium/tools/depot_tools.git
 .RE

man/src/depot_tools_tutorial.txt

@@ -96,8 +96,8 @@ extract it somewhere.
 extract the hidden ``.git'' folder which is necessary for 'depot_tools' to
 autoupdate itself. You can use ``Extract all...'' from the context menu though.
 
-Add 'depot_tools' to the 'end' of your PATH. Assuming you unzipped the
-bundle to `C:\workspace\depot_tools`:
+Add 'depot_tools' to the 'start' of your PATH (must be ahead of any installs of
+Python). Assuming you unzipped the bundle to `C:\workspace\depot_tools`:
 
 With Administrator access: ::
   *Control Panel -> System and Security -> System -> Advanced system settings*
@@ -107,7 +107,7 @@ Modify the PATH system variable to include `C:\workspace\depot_tools`.
 Without Administrator access: ::
   *Control Panel -> User Accounts -> User Accounts -> Change my environment variables*
 +
-Add a PATH user variable: `%PATH%;C:\workspace\depot_tools`.
+Add a PATH user variable: `C:\workspace\depot_tools;%PATH%`.
 
 From a `cmd.exe` shell, run the command `gclient` (without arguments). On first
 run, gclient will install all the Windows-specific bits needed to work with the
@@ -121,10 +121,10 @@ code, including msysgit and python.
 * If you see strange errors with the file system on the first run of gclient,
   you may want to link:http://tortoisesvn.tigris.org/faq.html#cantmove2[disable
   Windows Indexing].
-* If you are running Windows XP and see errors like ``The system cannot execute
-  the specified program'', try installing the
-  link:http://code.google.com/p/chromium/issues/detail?id=75886[``Microsoft
-  Visual C++ 2008 Redistributable Package''].
+* After running gclient open a command prompt and type `where python` and confirm that
+  the depot_tools python.bat comes ahead of any copies of python.exe. Failing to ensure
+  this can lead to overbuilding when using gn - see
+  link:https://bugs.chromium.org/p/chromium/issues/detail?id=611087[crbug.com/611087].
 =====
 endif::backend-xhtml11[]