My environment : 8G RAM, Windows 7 64bit

Official document 

http://dev.chromium.org/developers/how-tos/build-instructions-windows

1. Install depot_tool

            https://src.chromium.org/svn/trunk/tools/depot_tools.zip

            Download and unpack to any folder you like, such as C:\Work\depot_tools

               

            Note:

            * Do not use drag-n-drop or copy-n-paste extract from Explorer

            * Do not extract to a path containing spaces.

            

             Add a PATH user variable: %PATH%;C:\path\to\depot_tools

2. Initialize gclient

            Start -> cmd

            Execute gclient --version twice, twice is must.
            gclient --version

            gclient --version

3. Get source code

            Create a folder such as D:\Work\chromium

            Open cmd window
            cd D:\Work\chromium

            

            Get code

            fetch –nohooks chromium

            Create a branch named master 

            (The master is different with origin/master)

            cd src

            git checkout master

            Install some necessary tools by gclient

            gclient sync

4. Build code
            set GYP_DEFINES=component=shared_library
            python build\gyp_chromium
            ninja -C out\Debug chrome.exe

l   Trouble Shooting:

Error (gclient sync)

Running sdksetup.exe to download Win8 SDK (may request elevation)...

Windows 8 SDK failed to download, retrying.

Windows 8 SDK failed to download, retrying.

Windows 8 SDK failed to download, retrying.

Windows 8 SDK failed to download, retrying.

Windows 8 SDK failed to download, retrying.

Solution

Remove proxy setting.

Error (gclient sync)

Error: Command svn checkout https://cld2.googlecode.com/svn/trunk@157 D:\Blink\src\src\third_party\cld_2\src --revision 157 --non-interactive --force --ignore-externals returned non-zero exit status 1 in D:\Blink\src

Solution
        Execute svn ls https://cld2.googlecode.com/svn/trunk,choose 'accept' for conflict prompt.

Error (build code)

Warning C4819: The file contains a character that cannot be represented in the current code page (932). Save the file in Unicode format to prevent data loss

Solution

        You may use Chinese, Japanese or Korean Windows, and uses DBCS code page.

        You need to change your Windows system code page to English or another SBCS code page. You can do this by Control Panel - Regions - Administrative - Language for non-Unicode programs.

Debug

1.      Execute out\Debug\chrome.exe

2.      Start Visual Studio (Any version)

3.      In Visual Studio menu bar, Select Tool->Attach to Process-> Select the chrome process.

4.      Pull a file you want to set breaking point into Visual Studio and enjoy it.